Dictionary of Medical Acronyms & Abbreviations

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[ O ]

  O1 | O1 | O2 | O3
  • O  blood type in the ABO blood group; eye [Lat. oculus]; nonmotile strain of microorganisms [Ger. ohne Hauch]; no response [pacemaker]; objective findings; observed frequency in a contingency table; obstetrics; obvious; occipital electrode placement in electroencephalography; occiput; occlusal; [doctor's] office; often; ohm; old; opening; operator; operon; opium; oral, orally; orange [color]; orderly respirations [anesthesia chart]; ortho-; orthopedics; osteocyte; other; output; ovine; oxygen; pint [Lat. octarius]; respirations [anesthesia chart]; zero
  • O2  both eyes; diatomic oxygen; molecular oxygen
  • O3  ozone
  • O125  nonmucinous ovarian tumor antigen
  • o  eye [Lat. oculus]; opening; ovary transplant; pint [Lat. octarius]; see omicron
  •   negative; without
  • ο  see omicron
  • Ω  see omega
  • ω  see omega
  • OA  [o]esophageal atresia; obstructive apnea; occipital artery; occipito-anterior; occiput anterior; occupational asthma; octanoic acid; ocular albinism; old age; okadaic acid; oleic acid; on admission or arrival; open appendectomy; opiate analgesia; ophthalmic artery; opsonic activity; optic atrophy; oral airways; oral alimentation; organic anion; orotic acid; osteoarthritis; osteoarthrosis; ovalbumin; ovarian antibody; overall assessment; Overeaters Anonymous; oxalic acid
  • O&A  observation and assessment
  • O2a  oxygen availability
  • OAA  Old Age Assistance; Older Americans Act; Opticians Association of America; oxaloacetic acid
  • OAAD  ovarian ascorbic acid depletion
  • OAAS  observer's assessment alertness/sedation scale
  • OAAV  ovine adeno-associated virus
  • OAdV  ovine adenovirus
  • OAdV-A, B, C  ovine adenoviruses A, B, C
  • OAB  old age benefits
  • OABP  organic anion binding protein
  • OA/BVM  oral airway/bag-valve-mask
  • OAC  omeprazole, amoxicillin, clarithromycin
  • OACT  occupational activity [UMLS]
  • OAD  obstructive airway disease; organic anionic dye
  • OADC  oleate-albumin-dextrose-catalase [medium]
  • OAE  otoacoustic emission
  • OAF  off-axis factor; off-axis ratio [radiotherapy]; open air factor; osteoclast activating factor
  • OAFNS  oculo-auriculofrontonasal syndrome
  • OAG  open angle glaucoma
  • OAH  ovarian androgenic hyperfunction
  • OAIS  Outcomes and Information Set
  • OAISO  overaction of the ipsilateral superior oblique
  • OAK  Kjer optic atrophy
  • OALF  organic acid labile fluid
  • OALL  ossification of anterior longitudinal ligament
  • OAM  Office of Alternative Medicine [NIH]; outer acrosomal membrane
  • OAP  Office of Adolescent Pregnancy; old age pension, old age pensioner; ophthalmic artery pressure; osteoarthropathy; oxygen at atmospheric pressure; precocious osteoarthrosis
  • OAPP  Office of Adolescent Pregnancy Programs
  • OAR  organ at risk; Ottawa ankle rule
  • OARS  older Americans resources and services; Optimal Atherectomy Restenosis Study
  • OAS  old age security; oral allergy syndrome; osmotically active substance
  • OASD  ocular albinism-sensorineural deafness [syndrome]
  • OASDHI  Old Age, Survivors, Disability and Health Insurance
  • OASDI  Old Age Survivors and Disability Insurance
  • OASI  Old Age and Survivors Insurance
  • OASIS  Older Adults Service and Information System; Organization to Assess Strategies for Ischemic Syndromes; Outcome and Assessment Information Set
  • OASP  organic acid soluble phosphorus
  • OAstV  ovine astrovirus
  • OAT  O-acetyltransferase; Ochanomizu Aspirin Trial; Open Artery Trial; organic anion transporter; ornithine aminotransferase
  • OATL  ornithine aminotransferase-like
  • OATR  organism attribute [UMLS]
  • OAV  oculoauriculovertebral [dysplasia]
  • OAVS  oculo-auriculovertebral syndrome
  • OAVD  oculoauriculovertebral dysplasia
  • OAW  oral airways
  • OB  obese [mouse]; obese, obesity; objective benefit; obliterative bronchiolitis; obstetrics, obstetrician; occult bacteremia; occult bleeding; olfactory bulb; oligoclonal band
  • O&B  opium and belladonna
  • ob  obese [mouse]
  • OBAD  optimal biologically active dose
  • OBB  own bed bath; oriented bounding boxes
  • OBD  organic brain disease
  • OBCAM  opioid-binding cell adhesion molecule
  • OBE  Office of Biological Education
  • OBET  odor-baited entry trap
  • OBF  organ blood flow
  • OBG, ObG  obstetrics and gynecology, obstetrician-gynecologist
  • OBGS  obstetrical and gynecological surgery
  • OB-GYN, ob-gyn  obstetrics and gynecology, obstetrician-gynecologist
  • obj  objective
  • obl  oblique
  • OBMT  omeprazole, bismuth, metronidazole, tetracycline
  • OBOV  Obodhiang virus
  • OBP  odorant-binding protein; ova, blood, parasites [in stool]
  • OBR  obesity gene receptor
  • OBRA  Omnibus Reconciliation Act
  • OBS  obesity; obstetrical service; organic brain syndrome
  • Obs  observation, observed; obstetrics, obstetrician
  • obs  obsolete
  • Obst  obstetrics, obstetrician
  • obst, obstr  obstruction, obstructed
  • OB-US  obstetrical ultrasound [examination of the fetus]
  • OC  obstetrical conjugate; occlusocervical; oesophageal candidiasis; office call; on call; only child; optic chiasma; oral contraceptive; orbicularis oculi [muscle]; order communication [system]; original claim; organ culture; orofacial cleft; outer canthal [distance]; ovarian cancer; oxygen consumed
  • O&C  onset and course
  • OCA  octylcyanoacrylate; oculocutaneous albinism; olivopontocerebellar atrophy; oral contraceptive agent
  • OCa  ovarian carcinoma
  • OCAD  occlusive carotid artery disease
  • O2cap  oxygen capacity
  • OCB  obsessive-compulsive behavior
  • OCBAS  Optimal Coronary Balloon Angioplasty vs Stent [trial]; Optimal Coronary Balloon Angioplasty with Provisional Stenting vs Primary Stent [trial]
  • OCBF  outer cortical blood flow
  • OCC  object-centered coordinate [method]; oculocerebrocutaneous [syndrome]; operable case based reasoning [CBR]-oriented case; optimum care committee; oral cholecystography; original component complexes
  • occ  occasional; occiput, occipital; occlusion, occlusive; occupation; occurrence
  • occas  occasional
  • OCCI  oblique clear corneal incision
  • occip  occiput, occipital
  • occl  occlusion, occlusive
  • OCCPR  open chest cardiopulmonary resuscitation
  • OccTh  occupational therapy, occupational therapist
  • occ ther  occupational therapist or therapy
  • occup  occupation, occupational
  • occup Rx  occupational therapy
  • OCCV  object-centered coordinate [OCC] values
  • OCD  obsessive compulsive disorder; Office of Child Development; Office of Civil Defense; osteochondritis dissecans; ovarian cholesterol depletion; oxygen cost diagram
  • OCDD  octachlorodibenzo-p-dioxin
  • OCF  occipito-frontal [circumference]
  • OCG  omnicardiogram; oral cholecystogram
  • OCH  oral contraceptive hormone
  • OCHAMPUS  Office of Civilian Health and Medical Programs of the Uniformed Services [database]
  • OCHS  Office of Cooperative Health Statistics
  • OCIS  Oncology Clinical Information System
  • OCLC  Ohio Computer Library Center; online computer library center
  • OCM  oral contraceptive medication
  • OCN  oculomotor nucleus; oncology certified nurse; osteocalcin
  • OCOA  Online Cytogenetics of Animals
  • OCP  octacalcium phosphate; ocular cicatricial pemphigoid; Onchocerciasis Control Programme [Africa]; oral case presentation; oral contraceptive pill
  • OC&P  ova, cysts, and parasites
  • OCPD  obsessive compulsive personality disorder
  • OCPE  office of clinical practice evaluation
  • OCR  oculocardiac reflex; oculocerebrorenal [syndrome]; optical character reader; optical character recognition
  • oCRF  ovine corticotropin-releasing factor
  • OCRG  oxycardiorespirography
  • oCRH  ovine corticotropin-releasing hormone
  • OCRL  oculocerebrorenal [syndrome] of Lowe
  • OCRM  OpenGALEN Common Reference Model
  • OCRS  oculocerebrorenal syndrome
  • OCS  occipital condyle syndrome; Ondine's curse syndrome; open canalicular system; oral contraceptive steroid; order communication system; outpatient clinic substation; Oxford Cholesterol Study
  • OCSD  oculocraniosomatic disease
  • OCSI  orthostatic change in shock index
  • OCSP  Oxfordshire Community Stroke Project
  • OCT  object classification test; optical coherence tomography; optimal cutting temperature; oral cavity tumor; oral contraceptive therapy; organic cation transporter; ornithine carbamoyltransferase; orthotopic cardiac transplantation; outer canthal distance; oxytocin challenge test
  • O-CT  ortho-computed tomography
  • OCTD  overlap connective tissue disease
  • OCTM  open cavity tympanomastoidectomy
  • OCU  observation care unit
  • OCV  ordinary conversational voice
  • OD  Doctor of Optometry; object dictionary; obtained absorbance; occipital dysplasia; occupational dermatitis; occupational disease; oculodynamic; Ollier disease; on duty; once a day; open drop [anesthesia]; optical density; optimal dose; originally derived; out-of-date; outside diameter; overdose, overdosage; right eye [Lat. oculus dexter]
  • O-D  obstacle-dominance
  • OD-1  Organ Disease 1 [coronary atherosclerosis multicenter study]
  • OD-2  Organ Disease 2 [cerebrovascular atherosclerosis multicenter study]
  • O2D  oxygen delivery
  • ODA  office document architecture; open document architecture; overall disease assessment; right occipitoanterior [fetal position, Lat. occipito-dextra anterior]
  • ODB  opiate-directed behavior
      O0 | O1 | O2 | O3