What does o stand for?

Deamino [As substituent on nucleoside] [Biochemistry]

Oath (GEAB)

Oil (VRA)

Options [Computer science] [Telecommunications]

Organ

Origin (IDOE)

Ortho [Chemistry]

Other [Therapy term] (CTAA)

Out (VLIE)

Output (IDOE)

Overruled [Ruling in cited case expressly overruled] [Used in Shepard's Citations] [Legal term] (DLA)

Absence of Sex Chromosome (DAVI)

Angel (SAUS)

An Oige [The Irish Youth Hostels Association] [Founded in 1931]

Center of the Earth (SAUS)

Cleared to the Outer Marker (SAUS)

for those innocent souls (SAUS)

Horizontal Opposed [Aircraft engine]

Law Opinions [A publication] (DLA)

New Orleans [Louisiana] [Mint mark, when appearing on US coins] [Obsolete]

None (DAVI)

Nonmotile [Laboratory science] (DAVI)

Oasis

Oath

Oberst [Colonel] [German military - World War II]

Obiit [He, or She, Died] [Latin]

Object

Objective

Oblast [Governmental subdivision in USSR corresponding to a province or state]

Oboe [Phonetic alphabet] [World War II] (DSUE)

Observation Aircraft [Designation for all US military aircraft]

Observer

Obsolescent (AFIT)

Obstetrics [Medicine] (MAE)

Obvious (STED)

Occasional [Concerning occurrence of species]

Occidental

Occipital (STED)

Occiput [Medicine]

Occlusal [Dentistry]

Occupation (ADA)

Occurrence

Ocean [Maps and charts]

Oceanic (SAUS)

Oceanic Steamship Company (SAUS)

Octal [Number system with a base of eight] [Computer science] (BUR)

Octarius [Pint] [Pharmacy]

Octavo [Book from 20 to 25 centimeters in height] [Bibliography]

October

Octupole [Physics] (OA)

Oculus [Eye] [Latin]

Oddfellows (ODA)

Odericus [Flourished, 1166-1200] [Authority cited in pre-1607 legal work] (DSA)

Of [Telegraphy] (PCTE)

Off

Offered [Stock exchange term] (SPSG)

Office [or Officer]

Office of Operations [Coast Guard]

Office Technology Management Association (EA)

Official [Rate] [Value of the English pound]

Often (STED)

Ohio

Ohio Reports [A publication] (DLA)

Ohio State Library, Columbus, OH [Library symbol] [Library of Congress] (LCLS)

Ohm [Electricity]

Ohne [Antigen] [Immunology]

Oil

Oklahoma (DLA)

Old

Olivine Subgroup [Fayalite, forsterite] [CIPW classification] [Geology]

Oman (MILB)

Omicron [Fifteenth letter of the Greek alphabet] (NASA)

Omnipol Foreign Trade Corp. [Former Czechoslovakia] [ICAO aircraft manufacturer identifier] (ICAO)

Omnivore

Oncovin [Leurocristine, Vincristine] [Also, LCR, V, VC, VCR] [Antineoplastic drug]

Ongoing

Only

Ontario (DLA)

Ontario Reports [A publication] (DLA)

Ontario Securities Commission [Canada]

Opacity (MCD)

Open [Dancing position]

Open-Air Places [Parks, pools, etc.] [Public-performance tariff class] [British]

Open Circuit

Opening

Operand [Computer science]

Operating Room Attendant [Ranking title] [British Royal Navy]

Operation

Operator

Operon [Genetics]

Ophthalmology [Medical Officer designation] [British]

Opium [Slang]

Optimus [Best] [Latin]

Optional Dishes [School meals] [British]

Oral [Medicine]

Orange [Color] [Medicine] (DMAA)

Orange [Phonetic alphabet] [Royal Navy] [World War I] [Pre-World War II] (DSUE)

Orange [Maps and charts]

Orbit [Medicine] (DAVI)

Orchid Flowering [Horticulture]

Ordained

Order

Orderly [Medicine] (DAVI)

Orders Group [British military] (DMA)

Ordinance

Ordinary

Ordinary Level [School graduating grade] [British]

Ordinary Ray [Direction of]

Ordinate [Mathematics] (MSA)

Ordinis [By the Order Of] [Latin]

Ordnance

Ordonnanzoffizier [Special-Missions Staff Officer] [German military - World War II]

Ordovician [Paleontology] (QSUL)

Oregon (ROG)

Oregon Reports [A publication] (DLA)

Organ

Organic [Soil]

Organism [Psychology]

Organization

Organized Naval Reserve

Orient [Freemasonry]

Oriental

Oriented (IDYL)

Origin

Original

Original Response (DIPS)

Orotidine [One-letter symbol; see Ord]

Orthodox [Judaism]

Orthopedic (STED)

Os [Bone] [Latin]

Oscar [Phonetic alphabet] [International] (DSUE)

Oscillation or Fluctuation in Behavior [Psychology]

Oscillators [JETDS nomenclature] [Military] (CET)

Osphradium [An organ in mollusks]

Osten [East] [German]

Osteocyte (MELL)

Ostiole [Biology]

Other

Other Program (NTCM)

Otto's United States Supreme Court Reports [91-107 United States] [A publication] (DLA)

Ouest [West] [French]

Out

Outboard (DS)

Outfield [Baseball]

Outlay (GFGA)

Outlet

Output (BUR)

Outside Cylinders [Trains] [British]

Outside Edge [Skating]

Outstanding (ADWA)

Ovary

Ovation (WGA)

Oven

Over

Overall (IAA)

Overall Rating [Broadcasting]

Overcast

Overflow (VLIE)

Overseer

Ovulation

Ovule [Botany]

Owner

Oxford [County borough in England]

Oxidative (STED)

Oxygen [Chemical element]

Oxygenium (SAUS)

Realty Income Corp. [NYSE symbol] (SAG)

Respirations [on anesthesia chart] (DAVI)

Shoulder Season [Airline fare code]

Solicitor's Opinion [A publication] (DLA)

South African Law Reports, Orange Free State Provincial Division [1910-46] [A publication] (DLA)

Without Film [Bacteriology] (DAVI)