Abbreviations Complete Name
(H)eNB eNB or HeNB
1xCSFB Circuit Switched Fallback to 1xRTT
4C-HSDPA Four-Carrier HSDPA. HSDPA operation configured on 3 or 4 DL carriers.
5GC 5G Core Network
5GS 5G System
5QI 5G QoS Identifier
ABS Almost Blank Subframe
AC Access Category
ACK Acknowledgement
ACLR Adjacent Channel Leakage Ratio
ACLR Adjacent Channel Leakage power Ratio
ACS Adjacent Channel Selectivity
A-CSI Aperiodic CSI
AICH Acquisition Indication Channel
AKA Authentication and Key Agreement
AM Acknowledged Mode
AMBR Aggregate Maximum Bit Rate
AMC Adaptive Modulation and Coding
AMF Access and Mobility Management Function
AMR Codec Adaptive Multi-Rate Codec
ANDSF Access Network Discovery and Selection Function
ANR Automatic Neighbour Relation
API Application Program Interface
APN Access Point Name
ARP Allocation and Retention Priority
ARQ Automatic Repeat Request
AS Access Stratum
AS Application Server
AUL Autonomous Uplink
BA Bandwidth Adaptation
BCCH Broadcast Control Channel
BCH Broadcast Channel
BCSM Basic Call State Model
BER Bit Error Ratio
BG Border Gateway
BGCF Breakout Gateway Control Function
BH Backhaul
BL Bandwidth reduced Low complexity
BLER Block Error Ratio
BPSK Binary Phase Shift Keying
BR-BCCH Bandwidth Reduced Broadcast Control Channel
BS Bearer Service
BSR Buffer Status Report
C/I Carrier-to-Interference Power Ratio
CA Carrier Aggregation
CAG Closed Access Group
CAMEL Customised Application Mobile Enhanced Logic
CAP Camel Application Part
CAPC Channel Access Priority Class
CAZAC Constant Amplitude Zero Auto-Correlation
CBC Cell Broadcast Center
CBRA Contention Based Random Access
CC Component Carrier
CCE Control Channel Element
CDR Charging Data Record
CD-SSB Cell Defining SSB
CFRA Contention Free Random Access
CG Cell Group
CHO Conditional Handover
CIF Carrier Indicator Field
CIoT Cellular Internet of Things
CLI Cross Link interference
CMAS Commercial Mobile Alert Service
CMC Connection Mobility Control
CN Core Network
CoMP Coordinated Multi Point
CORESET Control Resource Set
CP Cyclic Prefix
CPC Conditional PSCell Change
C-plane Control Plane
CQI Channel Quality Indicator
CRC Cyclic Redundancy Check
CRE Cell Range Extension
C-RNTI Cell RNTI
CRS Cell-specific Reference Signal
CS Circuit Switched
CSA Common Subframe Allocation
CSCF Call Session Control Function
CSE CAMEL Service Environment
CSG Closed Subscriber Group
CSI Channel State Information
CSI-IM CSI interference measurement
CSI-RS CSI reference signal
CW Continuous Wave (un-modulated signal) 
DAG Directed Acyclic Graph
DAPS Dual Active Protocol Stack
DB-DC-HSDPA Dual Band Dual Cell HSDPA
DB-DC-HSUPA Dual Band Dual Cell HSUPADC-HSDPA Dual Cell HSDPA
DC Dual Connectivity
DCCH Dedicated Control Channel
DCH Dedicated Channel, which is mapped into Dedicated Physical Channel. 
DC-HSUPA Dual Cell HSUPA
DCI Downlink Control Information
DCN Dedicated Core Network
DCP DCI with CRC scrambled by PS-RNTI
DeNB Donor eNB
DFT Discrete Fourier Transform
DFTS DFT Spread OFDM
DHCP Dynamic Host Configuration Protocol
DIP Dominant Interferer Proportion ratio 
DL Down Link (forward link)
DL-AoD Downlink Angle-of-Departure
DL-SCH Downlink Shared Channel
DL-TDOA Downlink Time Difference Of Arrival
DMRS Demodulation Reference Signal
DMTC Discovery Signal Measurement Timing Configuration
DNN Data Network Name
DNS Domain Name System
DPCCH Dedicated Physical Control Channel
DPCH Dedicated Physical Channel
DPDCH Dedicated Physical Data Channel
DRB Data Radio Bearer
DRS Discovery Reference Signal
DRX Discontinuous Reception
DTCH Dedicated Traffic Channel
DTX Discontinuous Transmission
DwPTS Downlink Pilot Time Slot
EAB Extended Access Barring
E-AGCH E-DCH Absolute Grant Channel
ECGI E-UTRAN Cell Global Identifier
E-CID Enhanced Cell-ID (positioning method)
ECM EPS Connection Management
ECN Explicit Congestion Notification
E-DCH Enhanced Dedicated Channel 
E-DPCCH E-DCH Dedicated Physical Control Channel
E-DPDCH E-DCH Dedicated Physical Data Channel
EDT Early Data Transmission
EHC Ethernet Header Compression
E-HICH E-DCH HARQ ACK Indicator Channel
eHRPD enhanced High Rate Packet Data
eIMTA Enhanced Interference Management and Traffic Adaptation
EIRP Effective Isotropic Radiated Power
EMM EPS Mobility Management
eNB E-UTRAN NodeB
eNodeB (eNB) E-UTRAN Node B, Radio Base Station in LTE
ENUM E.164 Number Mapping
EPC Evolved Packet Core
EPDCCH Enhanced Physical Downlink Control Channel
EPS Evolved Packet System
E-RAB E-UTRAN Radio Access Bearer
E-RGCH E-DCH Relative Grant Channel
ETWS Earthquake and Tsunami Warning System
E-UTRA Evolved UTRA
E-UTRAN Evolved UTRAN
FACH Forward Access Channel
FDD Frequency Division Duplex
FDM Frequency Division Multiplexing
GBR Guaranteed Bit Rate
GERAN GSM EDGE Radio Access Network
GFBR Guaranteed Flow Bit Rate
GGSN Gateway GPRS Support Node
GLMS Group and List Management Server
GMLC Gateway Mobile Location Centre
gNodeB (gNB) 5G Node B, Radio Base Station in 5G
GNSS Global Navigation Satellite System
GP Guard Period
GRE Generic Routing Encapsulation
G-RNTI Group RNTI
GRUU Globally Routable User Agent URI
GSM Global System for Mobile communication
GUMMEI Globally Unique MME Identifier
GUP Generic User Profile
GUTI Globally Unique Temporary Identifier
GWCN GateWay Core Network
GWUS Group Wake Up Signal
HARQ Hybrid Automatic Repeat Request
HO Handover
HPLMN Home Public Land Mobile Network
HRNN Human-Readable Network Name
HRPD High Rate Packet Data
HSDPA High Speed Downlink Packet Access
HS-DPCCH Dedicated Physical Control Channel (uplink) for HS-DSCH 
HS-DPCCH2 Secondary Dedicated Physical Control Channel (uplink) for HS-DSCH
HS-DSCH High Speed Downlink Shared Channel
H-SFN Hyper System Frame Number
HS-PDSCH High Speed Physical Downlink Shared Channel
HSS Home Subscriber Server
HS-SCCH High Speed Shared Control Channel
HSUPA High Speed Uplink Packet Access
I CSCF Interrogating CSCF
IAB Integrated Access and Backhaul
IBCF Interconnection Border Control Function
ICIC Inter-Cell Interference Coordination
IDC In-Device Coexistence
IETF Internet Engineering Task Force
II-NNI Inter-IMS Network to Network Interface
IM IP Multimedia
IMC IMS Credentials
IMS IP Multimedia Core Network Subsystem
IMS ALG IMS Application Level Gateway
IMSI International Mobile Subscriber Identifier
IN Intelligent Network
INT-RNTI Interruption RNTI
IP Internet Protocol
IP CAN IP-Connectivity Access Network
IP SM GW IP Short Message Gateway
IPv4 Internet Protocol version 4
IPv6 Internet Protocol version 6
I-RNTI Inactive RNTI
ISDN Integrated Services Digital Network
ISIM IMS SIM
ISM Industrial, Scientific and Medical
ISP Internet Service Provider
ISUP ISDN User Part
IWF Interworking Function
KPAS Korean Public Alert System
LAA Licensed-Assisted Access
LB Load Balancing
LBT Listen Before Talk
LCG Logical Channel Group
LCR Low Chip Rate
LCS LoCation Service
LDPC Low Density Parity Check
L-GW Local Gateway
LHN Local Home Network
LHN ID Local Home Network ID
LIPA Local IP Access
LMU Location Measurement Unit
LPPa LTE Positioning Protocol Annex
LTE Long Term Evolution
LWA LTE-WLAN Aggregation
LWAAP LTE-WLAN Aggregation Adaptation Protocol
LWIP LTE WLAN Radio Level Integration with IPsec Tunnel
LWIP-SeGW LWIP Security Gateway
MAC Medium Access Control
MAP Mobile Application Part
MBMS Multimedia Broadcast Multicast Service
MBR Maximum Bit Rate
MBSFN Multimedia Broadcast multicast service Single Frequency Network
MCCH Multicast Control Channel
MCE Multi-cell/multicast Coordination Entity
MCG Master Cell Group
MCH Multicast Channel
MCS Modulation and Coding Scheme
MDBV Maximum Data Burst Volume
MDT Minimization of Drive Tests
MeNB Master eNB
MER Message Error Ratio
MFBR Maximum Flow Bit Rate
MGCF Media Gateway Control Function
MGF Media Gateway Function
MGW Media Gateway
MIB Master Information Block
MICO Mobile Initiated Connection Only
MIMO Multiple Input Multiple Output
MME Mobility Management Entity
MMTEL Multimedia telephony
MNO Mobile Network Operator
MO-EDT Mobile Originated Early Data Transmission
MPDCCH MTC Physical Downlink Control Channel
MRB Media Resource Broker
MRFC Multimedia Resource Function Controller
MRFP Multimedia Resource Function Processor
MSA MCH Subframe Allocation
MSI MCH Scheduling Information
MSP MCH Scheduling Period
MT Mobile Termination
MTC Machine-Type Communications
MTCH Multicast Traffic Channel
MT-EDT Mobile Terminated Early Data Transmission
MTSI Multimedia Telephony Service for IMS
Multi-RTT Multi-Round Trip Time
MU-MIMO Multi User MIMO
N2 Reference point between the NG-RAN and the AMF
NA(P)T-PT Network Address (Port-Multiplexing) Translation-Protocol Translation
NACK Negative Acknowledgement
NAI Network Access Identifier
NAPT Network Address Port Translation
NAS Non-Access Stratum
NAT Network Address Translation
NB-IoT Narrow Band Internet of Things
NCC Next Hop Chaining Counter
NCGI NR Cell Global Identifier
NCR Neighbour Cell Relation
NCRT Neighbour Cell Relation Table
NGAP NG Application Protocol
NG-RAN NG Radio Access Network
NH Next Hop key
NID Network Identifier
NNSF NAS Node Selection Function
NP Number portability
NPBCH Narrowband Physical Broadcast channel
NPDCCH Narrowband Physical Downlink Control channel
NPDSCH Narrowband Physical Downlink Shared channel
NPN Non-Public Network
NPRACH Narrowband Physical Random Access channel
NPRS Narrowband Positioning Reference Signal
NPSS Narrowband Primary Synchronization Signal
NPUSCH Narrowband Physical Uplink Shared channel
NR NR Radio Access
NRT Neighbour Relation Table
NSSS Narrowband Secondary Synchronization Signal
OFDM Orthogonal Frequency Division Multiplexing
OFDMA Orthogonal Frequency Division Multiple Access
OPI Offload Preference Indicator
OSA Open Services Architecture
OTDOA Observed Time Difference Of Arrival (positioning method)
P CSCF Proxy CSCF
P GRUU Public Globally Routable User Agent URI
PA Power Amplifier
PAPR Peak-to-Average Power Ratio
PBCH Physical Broadcast CHannel
PBR Prioritised Bit Rate
PCC Primary Component Carrier
PCC Policy and Charging Control
PCCH Paging Control Channel
P-CCPCH Primary Common Control Physical Channel
PCEF Policy and Charging Enforcement Function
PCell Primary Cell
PCFICH Physical Control Format Indicator CHannel
PCH Paging Channel
PCI Physical Cell Identifier
P-CPICH Primary Common Pilot Channel
PCRF Policy and Charging Rules Function
PDCCH Physical Downlink Control CHannel
PDCP Packet Data Convergence Protocol
PDN Packet Data Network
PDP Packet Data Protocol e.g., IP
PDSCH Physical Downlink Shared CHannel
PDU Protocol Data Unit
P-GW PDN Gateway
PHICH Physical Hybrid ARQ Indicator CHannel
PHY Physical layer
PICH Paging Indicator Channel
PLMN Public Land Mobile Network
PLMN Cell Public Land Mobile Network Cell
PMCH Physical Multicast CHannel
PMK Pairwise Master Key
PNI-NPN Public Network Integrated NPN
PO Paging Occasion
PPM Parts Per Million
PPPP ProSe Per-Packet Priority
PPPR ProSe Per-Packet Reliability
PRACH Physical Random Access CHannel
PRB Physical Resource Block
PRG Precoding Resource block Group
P-RNTI Paging RNTI
ProSe Proximity based Services
PSBCH Physical Sidelink Broadcast CHannel
PSC Packet Scheduling
PSCCH Physical Sidelink Control CHannel
PSCell Primary SCell
PSDCH Physical Sidelink Discovery CHannel
PSI Public Service Identity
PSK Pre-Shared Key
PSM Power Saving Mode
PS-RNTI Power Saving RNTI
PSS Primary Synchronisation Signal
PSSCH Physical Sidelink Shared CHannel
PSTN Public Switched Telephone Network
pTAG Primary Timing Advance Group
PTW Paging Time Window
PUCCH Physical Uplink Control CHannel
PUR Preconfigured Uplink Resource
PUSCH Physical Uplink Shared CHannel
PWS Public Warning System
QAM Quadrature Amplitude Modulation
QCI QoS Class Identifier
QFI QoS Flow ID
QoE Quality of Experience
QoS Quality of Service
QPSK Quadrature Phase Shift Keying
RA Random Access
RAB Radio Access Bearer
RAC Radio Admission Control
RACH Random Access Channel
RANAC RAN-based Notification Area code
RA-RNTI Random Access RNTI
RAT Radio Access Technology
RB Radio Bearer
RBC Radio Bearer Control
RCLWI RAN Controlled LTE-WLAN Interworking
REG Resource Element Group
RF Radio Frequency
RFC Request for Comments
RIBS Radio-interface based synchronization
RIM RAN Information Management
RIM Remote Interference Management
RLC Radio Link Control
RMSI Remaining Minimum SI
RMTC RSSI Measurement Timing Configuration
RN Relay Node
RNA RAN-based Notification Area
RNAU RAN-based Notification Area Update
RNC Radio Network Controller
RNL Radio Network Layer
RNTI Radio Network Temporary Identifier
ROHC Robust Header Compression
ROM Receive Only Mode
R-PDCCH Relay Physical Downlink Control CHannel
RQA Reflective QoS Attribute
RQoS Reflective Quality of Service
RRC Radio Resource Control
RRM Radio Resource Management
RS Reference Signal
RSRP Reference Signal Received Power
RSRQ Reference Signal Received Quality
RSSI Received Signal Strength Indicator
RSTD Reference Signal Time Difference
RU Resource Unit
S CSCF Serving CSCF
S GW Signalling Gateway
S1-MME S1 for the control plane
S1-U S1 for the user plane
SAE System Architecture Evolution
SAP Service Access Point
SBCCH Sidelink Broadcast Control Channel
SCC Secondary Component Carrier
S-CCPCH Secondary Common Control Physical Channel.
SCell Secondary Cell
SC-FDMA Single Carrier – Frequency Division Multiple Access
SCG Secondary Cell Group
SCH Synchronization Channel
SCH Synchronization Channel consisting of Primary and Secondary synchronization channels
SC-MCCH Single Cell Multicast Control Channel
SC-MTCH Single Cell Multicast Transport Channel
SC-N-RNTI Single Cell Notification RNTI
SC-PTM Single Cell Point To Multiploint
SC-RNTI Single Cell RNTI
SCS Service Capability Server
SCTP Stream Control Transmission Protocol
SD Slice Differentiator
SDAP Service Data Adaptation Protocol
SDF Service Data Flow
SDMA Spatial Division Multiple Access
SDP Session Description Protocol
S-DPCCH Secondary Dedicated Physical Control Channel
SD-RSRP Sidelink Discovery Reference Signal Received Power
SDU Service Data Unit
S-E-DPCCH Secondary Dedicated Physical Control Channel for E-DCH
S-E-DPDCH Secondary Dedicated Physical Data Channel for E-DCH
SeGW Security Gateway
SeNB Secondary eNB
SFI-RNTI Slot Format Indication RNTI
SFN System Frame Number
SG Serving Grant
SGSN Serving GPRS Support Node
S-GW Serving Gateway
SI System Information
SIB System Information Block
SIM Subscriber Identity Module
SIP Session Initiation Protocol
SIPTO Selected IP Traffic Offload
SIPTO@LN Selected IP Traffic Offload at the Local Network
SIR Signal to Interference ratio
SI-RNTI System Information RNTI
SLA Service Level Agreement
SL-BCH Sidelink Broadcast Channel
SL-DCH Sidelink Discovery Channel
SLF Subscription Locator Function
SL-RNTI Sidelink RNTI
SL-SCH Sidelink Shared Channel
SMC Security Mode Command
SMF Session Management Function
SML Soft Metric Location (Soft channel bit)
SNPN Stand-alone Non-Public Network
SNPN ID Stand-alone Non-Public Network Identity
S-NSSAI Single Network Slice Selection Assistance Information
SPDCCH Short PDCCH
SPID Subscriber Profile ID for RAT/Frequency Priority
SPS Semi-Persistent Scheduling
SPT Short Processing Time
SPUCCH Short PUCCH
SR Scheduling Request
SRB Signalling Radio Bearer
SRS Sounding Reference Signal
S-RSRP Sidelink Reference Signal Received Power
SRVCC Single Radio Voice Call Continuity
SS Synchronization Signal
SS7 Signalling System 7
SSB SS/PBCH block
SSF Service Switching Function
SSS Secondary Synchronisation Signal
SST Slice/Service Type
sTAG Secondary Timing Advance Group
STCH Sidelink Traffic Channel
STTD Space Time Transmit Diversity
SU Scheduling Unit
SUL Supplementary Uplink
SU-MIMO Single User MIMO
T GRUU Temporary Globally Routable User Agent URI
TA Tracking Area
TA Timing Advance
TAG Timing Advance Group
TAS Telephony Application Server
TB Transport Block
TCP Transmission Control Protocol
TDD Time Division Duplex
TDD Time Division Duplexing
TDM Time Division Multiplexing
TEID Tunnel Endpoint Identifier
TFC Transport Format Combination
TFCI Transport Format Combination Indicator
TFT Traffic Flow Template
THIG Topology Hiding Inter-network Gateway
TM Transparent Mode
TMGI Temporary Mobile Group Identity
TNL Transport Network Layer
TPC Transmit Power Control
TPI Transmitted Precoding Indicator
TrGW Transition Gateway
TSTD Time Switched Transmit Diversity
TTI Transmission Time Interval
UAC Unified Access Control
UCI Uplink Control Information
UDC Uplink Data Compression
UE User Equipment
UL Uplink
UL Up Link (reverse link)
UL CLTD Up Link Closed-Loop Transmit Diversity
UL OLTD Up Link Open-Loop Transmit Diversity
UL-AoA Uplink Angles of Arrival
UL-RTOA Uplink Relative Time of Arrival
UL-SCH Uplink Shared Channel
UM Unacknowledged Mode
UMTS Universal Mobile Telecommunication System
UMTS Universal Mobile Telecommunications System
UPF User Plane Function
U-plane User plane
UpPTS Uplink Pilot Time Slot
URL Universal Resource Locator
URLLC Ultra-Reliable and Low Latency Communications
USIM UMTS SIM
UTRA Universal Terrestrial Radio Access
UTRA UMTS Terrestrial Radio Access
UTRAN Universal Terrestrial Radio Access Network
V2I Vehicle-to-Infrastructure
V2N Vehicle-to-Network
V2P Vehicle-to-Pedestrian
V2V Vehicle-to-Vehicle
V2X Vehicle-to-Everything
VRB Virtual Resource Block
WLAN Wireless Local Area Network
WT WLAN Termination
WUS Wake Up Signal
X2 GW X2 GateWay
X2-C X2-Control plane
X2-U X2-User plane
XnAP Xn Application Protocol
Xn-C Xn-Control plane
Xn-U Xn-User plane
Xw-C Xw-Control plane
Xw-U Xw-User plane

Major Source:

3GPP 36.300
3GPP 38.300
3GPP 23.228
3GPP 25.101