(n) octane value
(n) Ottoman (Osmanli) dynasty
(n) ottoman
(n) (uk) Anotogaster sieboldii (largest species of dragonfly in Japan)
(n) opinion
(P)
(n) offense
offence
(n) off-line
(n) off-ramp
(n) option
(P)
(n) opsonin
(n) (abbr) operational amplifier
(n) operant
(n) (comp) operand
(n) operon theory (Jacob & Monod, 1961)
(n) (comp) Orion
(n) Dutch (language)
(n) (uk) garden strawberry (Fragaria x ananassa)
(n) Orient
(P)
(n) (comp) ORIONS
(n) Orion
(n) Oryzanin (brand-name vitamin B1; extracted from rice)
(n) Olympia
(P)
(n) Olympus
(n) orthicon (early form of television camera tube)
(n) ornithine
(n) oleic acid
(n) olefin
olefine
alkene
(n) orange (colour, color)
(P)
(n) orotic acid
(n) on-site