O3DCLCC Oriented 3 Dimensionally Crosslinked Liquid Crystal Chiral
OA Osteo Arthritis
OAB Over Active Bladder
OAP Overrunning alternator pulleys
OAR Organs At Risk
OAS Orbital Atherectomy System
OAV Ovine Adeno Virus
OBD Opioid-induced Bowel Dysfunction
OBS Organic Based Stabilizer (PVC)
OBSH 4,4'-Oxy bis Benzene Sulfonyl Hydrazide
OBT Optimized Background Therapy
OCA O Carboxy Anhydride
OCBAL Ortho Chloro Benz AL dehyde
OCD Obsessive Compulsive Disorders
OCEB Ortho Chloro Ethyl Benzene
OCL Osteo Clast
OCRP Oral Controlled Release Patch
OCS Organosilanized Colloidal Silica
OCT Olefins Conversion Technology (Methathesis)
OCU Olefin Conversion Unit
OD 1,2-Octane Diol
OD Octa Decadienoic (acid)
ODAC Oncologic Drugs Advisory Committee (FDA)
ODC Ornithine De Carboxylase
ODC Oxygen Depolarised Cathode
ODC Oxygen Depleting Cathode
ODCB Ortho Di Chloro Benzene
ODD Oppositional Defiant Disorder
ODD Orally Disintegrating Dosage (Pharma.>Drug Delivery)
ODP Ozone Depletion Potential
ODPA 4,4'-Oxy Di (Phthalic Anhydride)
ODPEG Octa Decadienoic (acid) Poly Ethyleno Glycol (ester)
ODPEGSu ODPEG Succinic acid deriv.
ODT Orally Disintegrating Tablets
OEB Occupational Exposure Band
OED Oleoyl Estrone Developments
OEL Organic Electro Luminescence
OEL Occupational Exposure Limit
OEM Original Equipment Manufacturing
OFS Organic Formulated Stabilizer (PVC)
OGG Oxo Guanine Glycosylase
OHC Over Head Camshafts
OHP Organo Hydroxylase Phosphorus (Enzyme)
OHSV Oncolytic Herpes Simplex Virus
OHV Over Head Valves
OIC Opioid Induced Constipation
OIP Osteoclast Inhibitor Protein
OIT N-n-Octyl Iso Thiazolin-3-one (Biocides)
OL On Line
OLED Organic Light Emitting Diode
OLTP On Line Transaction Processing
OM Oral Mucositis
OMC Octyl Methoxy Cinnamate
OMD Oral Mucoadhesive Dosage
OMP Orotidine Mono Phosphate
OMRI Overhauser Magnetic Resonance Imaging
ONC Octa Nitro Cubane (Explosive)
ONR Office of Naval Research (USA)
OP Organo Phosphate
OPAA Organo Phosphorous Acid Anhydrolase
OPC Oro Pharyngeal Candidiasis
OPCW Organisation for the Prohibition of Chemical Weapons
OPG Osteo Prote Gerin (Protein)
OPH Organo Phosphorus Hydrolase
OPLC Over Pressured Layer Chromatography
OPO Optical Parametric Oscillator (Photonics)
OPP Ortho Phenyl Phenol (biocide)
OPP Oriented Poly Propylene (packaging film)
oPPV Oligo-P-PhenyleneVinylene
OPRD Organic Process Research & Development (ACS journal)
OPV Organic Photo Voltaics
OR Oil Repellency (textiles)
OR Operating Room (Surgery)
ORAC Oxygen Radical Absorption Capacity
ORC Oxidized Regenerated Cellulose
ORF Open Reading Frame (Coding part of DNA seq)
ORG ORGanic, ORGanization
ORL Opioid Receptor Like
OSA Obstructive Sleep Apnea
OSAB Oxidative Stressed Autologous Blood
OSB Oriented Strand Board
OSBAL Ortho Sulfonyl Benz AL dehyde
OSCS Over Sulfated Chondroitin Sulfate
OSDA Organic Structure Directing Agent
OSDF Oral Solid Dosage Formulation
OSHA Occupational Safety & Health Administration (USA)
OSN Organic Solvent Nanofiltration
OSRM Oxidative Steam Reforming of Methanol
OTC Over The Counter (Pharma.)
OTEC Ocean Thermal Energy Conversion
OTL Oxidized Transport Layer (semiconducting polymer system)
OTO Occupant To Occupant
OTP Ortho Tolyl Pentene
OTP One Time Programmable
OTPA Otonecine Type Pyrrolizidine Alkaloids
OTS n-Octyl Trichloro Silane
OVAT One Variable At a Time (Pharma. Process.)
OVD Ophthalmic ViscoSurgical Device
OVHS OVarian Histo Scanning