Occam's Razor
— Noun
– English
～ the principle that entities should not be multiplied needlessly; the simplest of two competing theories is to be preferred
out of reach
— Adjective
– English
～ inaccessibly located or situated; "an unapproachable chalet high in the mountains"; "an unreachable canyon"; "the unreachable stars"
oven-ready
— Adjective
– English
～ prepared before sale and ready to be cooked
object recognition
— Noun
– English
～ the visual perception of familiar objects
orange red
— Noun
– English
～ a variable color that is vivid red but sometimes with an orange tinge
oxblood red
— Noun
– English
～ a dark brownish-red color
orange-red
— Adjective
– English
～ of red tinged with orange
orangish-red
— Adjective
– English
～ of red tinged with orange
oxidation-reduction
— Noun
– English
～ a reversible chemical reaction in which one reaction is an oxidation and the reverse is a reduction
oxidation-reduction indicator
— Noun
– English
～ an indicator that shows a reversible color change between oxidized and reduced forms
over-refine
— Verb
– English
～ refine too much or with excess of subtlety; "He is overrefining this matter"
oil refinery
— Noun
– English
～ a refinery for petroleum
off-axis reflector
— Noun
– English
～ a reflecting telescope with the mirror slightly tilted to throw the image to the side where it can be viewed
oesophageal reflux
— Noun
– English
～ reflux of stomach contents into the esophagus
Osmunda regalis
— Noun
– English
～ large deeply rooted fern of worldwide distribution with upright bipinnate compound tufted fronds
on a regular basis
— Adverb
– English
～ in a regular manner; "letters arrived regularly from his children"
organized religion
— Noun
– English
～ an institution to express belief in a divine power; "he was raised in the Baptist religion"; "a member of his own faith contradicted him"
Ononis repens
— Noun
– English
～ European woody plant having pink flowers and unifoliate leaves and long tough roots; spreads by underground runners
on request
— Adverb
– English
～ on the occasion of a request; "advice was free for the asking"
operations research
— Noun
– English
～ research designed to determine most efficient way to do something