AA : Anti-Aircraft and Army Act

AA & QMG : Assistant Adjutant and Quartermaster General

AASC : Anti-Aircraft Searchlight Company

AASS : Anti-Aircraft Searchlight Section

AB : Army Book

ABPO : Advanced Base Post Office

ACG : Assistant Chaplain General

ACI : Army Council Instruction

ACC : Army Cyclist Corps

AD : (or Art. Dpt) Artillery Depot

ADAPS : Assistant Director Army Postal Services

ADC : Aide de Camp

ADGT : Assistant Director-General of Transportation

ADL : Assistant Director of Labour

ADLR : Assistant Director of Light Railways

ADMS : Assistant Director Medical Services

ADOS : Assistant Director Ordnance Services

ADRT : Assistant Director Railway Traffic

ADS : Advanced Dressing Station

ADTN : Assistant Director Transportation

ADVS : Assistant Director Veterinary Services

AEC : 9or A. Emp. Coy) Area Employment Company

AF : Army Form

AFA : Army Field Artillery, and Australian Field Artillery

AG : Adjutant General

AGS : Army Gymnastic Staff

AIF : Australian Imperial Force

AIS : Assistant Inspector of Searchlights

AMFO : Assistant Military Forwarding Officer

AMLO : Assistant Military Landing Officer

AMO : Administrative Medical Officer

AMS : Assistant Military Secretary

ANZAC : Australian and New Zealand Army Corps

AO : Army Order

AOC : Army Ordnance Corps

AOD : Army Ordnance Department

AP : Armour Piercing (ammunition)

APC : Army Pay Corps and Assistant Principal Chaplain

APM : Assistant Provost Marshal

APO : Army Post Office

AQMG : Assistant Quartermaster-General

ARMW : Army Reserve Munition Worker

ARD : Alberta Reinforcement Depot

ARP : Ammunition Refilling Point

ARS : Advanced Regulating Station

ASC : Army Service Corps

ASD : Army Schools Department

ASO : Area Searchlight Officer

ASP : (or Amm. Sub. Pk) Ammunition Sub-Park

AT : Army Troops

AVC : Army Veterinary Corps

BAC : Brigade Ammunition Column

BAPO : Base Army Post Office

BC : Battery Commander or Base Commandant

BCA : Battery Commander’s Assistant

Bdmr : Bandmaster

BG : Broad Gauge (railway)

BGGS : Brigadier-General General Staff

BGRA : Brigadier-General Royal Artillery

BL : Breech Loading

BLC : Breech Loading  Converted

BM : Brigade Major

BOR : British Other Rank

BRCS : British Red Cross Society

BSM : Battery Sergeant-Major

BWI : British West Indies Regiment

BWM : British War Medal

CB : Confinement to Barracks (punishment) and Counter-Battery

CBSO : Counter-Battery Staff Officer

CC : Confined to Camp (punishment)

CCCC : Cape Colony Cyclist Corps

CCD : Commander of Coast Defences

CCRA : Corps Commander Royal Artillery

CCS : Casualty Clearing Station

CDS : Corps Dressing Station

CE : Chief Engineer

CEF : Canadian Expeditionary Force

CEPC : Chief Engineer Port Construction

CF : Chaplain to the Forces

CFC : Canadian Forestry Commission

CGS : Chief of General Staff

CHA : Commander Heavy Artillery

CHDAVC : Convalescent Horse Depot Army Veterinary Corps  

CID : Committee of Imperial Defence

CIGS : Chief of the Imperial General Staff

CLC : Chinese Labour Corps

CLLE : Charger-Loading Lee-Enfield rifle

CLLM : Charger-Loading Lee-Metford rifle

CLRO : Corps Light Railway Officer

CME : Chief Mechanical Engineer

CMO : Court-Martial Officer

CMP : Corps of Military Police

CO : Commanding Officer, Conscientious Objector  

COO : Chief Ordnance Officer

CP : Censorship & Publicity

Cpl : Corporal (rank)

CQMS : Company Quartermaster Master Sergeant

CRA : Commanding Royal Artillery

CRCE : Chief Railway Construction Engineer

CRE : Commanding Royal Engineers

CRO : Corps Roads Officer

CSIC : Cadet School Infantry Company

CSM : Company Sergeant Major

CT : Communication Trench

CVBC : Cape Volunteer Bearer Corps

D of A : Director of Artillery

DA : Divisional Artillery

DAA : Director of Army Accounts

DAAG : Deputy Assistant Adjutant General

DAC  - Divisional Ammunition Column

DACG : Deputy Assistant Chaplain General

DADAPS : Deputy Assistant Director Army Postal Services

DADGR&E : Deputy Assistant Director of Graves Registration and Enquires

DADGT : Deputy Assistant Director-General of Transportation

DADL : Deputy Assistant Director of Labour

DADMS : Deputy Assistant Director Medical Services

DADOS : Deputy Assistant Director Ordnance Services

DADPS : Deputy Assistant Director Postal Services

DAD Roads : Deputy Assistant Director of Roads

DAD Sigs : Deputy Assistant Director of Signals

DADRT : Deputy Assistant Director Railway Traffic

DADS : Deputy Assistant Director Supplies

DADT : Deputy Assistant Director Transport

DADW : Deputy Assistant Director of Works

DAG : Deputy Adjutant General

DAMS : Deputy Assistant Military Secretary

DAP : Divisional Ammunition Park

DAPC : Deputy Assistant Principal Chaplain

DAPS : Director of Army Postal Services

DAQMG : Deputy Assistant Quartermaster General

DA & QMG : Deputy Adjutant and Quartermaster General

DBC : Director of Barrack Construction

DCIGS : Deputy Chief of the Imperial General Staff

DCM : Distinguished Conduct Medal

DDAPS : Deputy Director of Army Postal Services

DCM : District Court-Martial

DDGMR : Deputy Director-General Military Railways or Movements and Railways

DDGT : Deputy Director-General of Transportation

DDIWT : Deputy Director Inland Waterway Transport

DDMS : Deputy Director Medical Services

DDOS : Deputy Director Ordnance Services

DDRT : Deputy Director Railway Traffic

DD S and T : Deputy Director Supplies and Transport

DD Sigs : Deputy Director of Signals

DDTN : Deputy Director of Transportation

DDVS : Deputy Director Veterinary Services

DDW : Deputy Director of Works

DEOS : Director of Equipment and Ordnance Stores

DFC : Distinguished Flying Cross

DFS : Director of Financial Services

DFW : Director of Fortifications and Works

DGAMS : Director-General, Army Medical Services

DGAVS : Director-General, Army Veterinary Services

DGNS : Director-General National Service

DGO : Divisional Gas Officer

DGTF : Director-General of the Territorial Force

DIL : Dangerously Ill List

DIWD : Director Inland Waterways and Docks

DIY : Derbyshire Imperial Yeomanry

DLR : Director of Light Railways

DM : Director of Mobilisation

DMO : Director of Military Operations

DMS : Director of Medical Services, also  Deputy Military Secretary

DMT : Director of Military Training

DNTO : Divisional Naval Transport Officer

DORA : Defence of the Realm Act

DORE : District Office Royal Engineers

DOS : Director of Ordnance Services

DP : Drill Purpose

DPS : Director of Personal Services

DPW : Director of Prisoners of War

DQMG : Deputy Quartermaster-General

DR :  Director of Remounts, also Despatch Rider

DRF : Depression Range-Finder

DRG&E : Director of Graves Registration and Enquires

DRLS : Despatch Rider Letter Service

D Rlys : Director of Railways

DRO : Director of Recruiting and Organisation

DRT : Director Railway Traffic

DSC : Distinguished Service Cross (a naval decoration)

DSD : Director of Staff Duties

DSM : Distinguished Service Medal (a naval decoration)

DSO : Distinguished Service Order

DSQ : Director of Supplies and Quartering

DTM : Director of Transport and Movements

DTMO : Divisional Trench Mortar Officer

DTN : Director of Transportation

DW : Director of Works

EBSVR : East Bengal State Volunteer Rifles

EEF : Egyptian Expeditionary Force

EFC : Expeditionary Force Canteen

EinC : Engineer in Chief

ELC : Egyptian Labour Corps

E&M : Electrical and Mechanical

EMO : Embarkation Medical Officer

FANY : First Aid Nursing Yeomanry

FAO : Forward Area Officer (Light Railways)

FAU : Friends Ambulance Unit

FGCM : Field General Court-Martial

FLC : Fijian Labour Contingent (later Corps)

FOO : Forward Observation Officer

FP : Field Punishment

FPO : Field Post Office

FSC : Field Survey Company

FSL : Field Searchlight

FSM : Field Service Manual

FSR : Field Service Regulations

FWD : Four Wheel Drive

GCM : General Court-Martial

GHQ : General Headquarters

GMP : Garrison Military Police

GOC : General Officer Commanding

GOCinC : General Officer Commanding-in-Chief

GRC : Graves Registration Commission

GRO : General Routine Order

GRU : Graves Registration Unit

GS : General Service and General Staff

GSO : General Staff Officer

GSW : Gunshot Wound

HA : Heavy Artillery

HAR : Heavy Artillery Reserve

HBMGC : Heavy Branch Machine Gun Corps (later Tank Corps)

HE : High Explosive

HPD : Home Postal Depot

HS : Home Service

HSC : Hospital Ship Case (medical)

HT : Horse Transport

HV : High Velocity

IA : Indian Army

IAF : Independent Air Force

IE : Illegal enlistment

IGC : Inspector-General of Communications

IGT : Inspector-General of Transportation

IHL : Imprisonment with Hard Labour

IO : Intelligence Officer

IOM : Inspector of Ordnance Machinery

IOR : Indian Other Rank

IS : Inspector of Searchlights

IWGC : Imperial War Graves Commission

IWT : Inland Water Transport

IW&D : Inland Waterways and Docks

JAG : Judge Advocate General

KR : King’s Regulations

L/C or L/Cpl: Lance Corporal

LEE : London Electrical Engineers

LO : Liaison Officer

LofC : Lines of Communication

LR : Local Reserve

MAC : Motor Ambulance Convoy

MB : Medical Board

MC : MIlitary Cross

MDS : Main Dressing Station

MEF : Mediterranean Expeditionary Force

MFD : Military Forwarding Department

MFO : Military Forwarding Officer

MFP : Military Foot Police

MGC : Machine Gun Corps

MGGS : Major General General Staff

MGO -  Master-General of the Ordnance

MGRA : Major General Royal Artillery

MGS : Machine Gun School

MLO : Military Landing Officer

MM : Military Medal

MMGC : Motor Machine Gun Corps

MML : Manual of Military Law

MMP : Military Mounted Police

MPI : Mean Point of Impact

MPSC : Military Police Staff Corps

MS : Military Secretary

MSM : Meritorious Service Medal

MT : Mechanical Transport

MVC : Motor Volunteer Corps

MVS : Mobile Veterinary Section

NACB : National Army Catering Board

NCC : Non-Combatant Corps

NTO : Naval Transport Officer

NYD : Not Yet Diagnosed (medical term)

NYDN : Not Yet Diagnosed Nervous (medical term for suspected shell shock)

OC : Officer Commanding, Officer Cadet

OR : Other Rank

ORS : Orderly Room Sergeant

OTC : Officers Training Corps

PB : Permanent Base (medical)

PBI : Poor Bloody Infantry (colloquial)

P & BT : Physical and Bayonet Training

PC : Principal Chaplain (non Church of England)

PM : Provost Marshal

PNTO : Principal Naval Transport Officer

POW : Prisoner of War

PPCLI : Princess Patricia's Canadian Light Infantry

psc : Passed Staff College

Pte : Private (rank)

PU : Permanently Unfit (medical)

PUO : Pyrexia of Unknown Origin (medical term usually applied to Trench Fever)

QF : Quick Firing

QMAAC : Queen Mary’s Army Auxiliary Corps

QMG : Quartermaster General

QMS : Quartermaster Sergeant

Qs : Qualified for Staff

RAF : Royal Air Force

RAFA : Royal Australian Field Artillery

RAGA : Royal Australian Garrison Artillery

RAP : Regimental Aid Post

RCE : Railway Construction Engineer

RCO : Railway Control Officer

RDC : Royal Defence Corps

REPS : Royal Engineers Postal Section

RFA : Royal Field Artillery

RFC : Royal Flying Corps

RGA : Royal Garrison Artillery

RH - Railhead

RHA : Royal Horse Artillery, and Reserve Heavy Artillery

RM : Riding Master, and Royal Marines

RMA : Royal Marine Artillery

RMLC : Royal Marine Labour Corps

RMLI : Royal Marine Light Infantry

RNAS : Royal Naval Air Service

RND : Royal Naval Division (63 Div)

RO : Recruiting Officer

ROD : Railway Operating Division

ROO : Railway Ordnance Officer

RP : Rules of Procedure, Regimental Police, Refilling Point

RSM : Regimental Sergeant Major

RSO : Railhead Supply Officer

RTC : Reserve Training Centre

RTE : Railway Transport Establishment

RTO : Railway Transport Officer (later Railway Traffic Officer)

RTU : Returned to Unit

S - Service

SAA : Small Arms Ammunition

SANLC : South African Native Labour Corps

SC : Staff Captain

SCF : Senior Chaplain to the Forces

SD : Staff Duties

SGS : Surveyor-General of Supply

Sgt : Sergeant (rank)

SIW : Self-Inflicted Wound

Sjt : Serjeant (rank)

SLR : Superintendent of Light Railways

SMLE : Short Magazine Lee-Enfield

SOS : Struck off strength. Also used in usual sense (of emergency).

SP : Strongpoint

SPT : (preceding a man's number) Sportmen's Battalion Royal Fusiliers

SR : Special Reserve

SRS : Sound Ranging Section

SSM : Squadron Sergeant Major (cavalry)

STK : (preceding a man's number) Stockbroker's Battalion Royal Fusiliers

TAT : Temporary Ambulance Train

TB : Temporary Base (medical)

TC : Tank Corps

TCO : Train Conducting Officer

TDO : Telephone Dug-out

TEE : Tyne Electrical Engineers

TF : Territorial Force

TM : Trench Mortar

TMB : Trench Mortar Battery

TO : Transport Officer

TOS : Taken on strength

TR : Training Reserve

TRB : Training Reserve Brigade

TSM : Troop Sergeant Major (cavalry)

VAD : Voluntary Aid Detachment

VADGS : Voluntary Aid Detachment General Service

VC : Victoria Cross

VO : Veterinary Officer

VTC : Volunteer Training Corps

WAAC : Women’s Army Auxiliary Corps (later QMAAC)

WD : War Department

WE : War Establishment

WIR : West India Regiment

WO : War Office

WWCS : Walking Wounded Collecting Station

YOC : Young Officers Company

YS : Young Soldier