SUB

pref. under, beneath, below; secondary, subordinate; indicating that an ingredient in a compound is present in only a small proportion (Chemistry)

prep. under, beneath, below

v. replace, act as a substitute for, take the place of

n. (Informal) substitute; submarine; hero sandwich, submarine sandwich, sandwich made of a loaf of French or Italian bread cut in half lengthwise and filled with slices of meats or cheese and vegetables (lettuce, tomato, onion and condiments); subordinate; sublieutenant

Sub- is a prefix derived from Latin, meaning "under", "below", or "less than". The analogous Greek prefix is "hypo-". Antonym: supra.As a word, sub is an abbreviation for:SubmarineSubmarine sandwichSubscriberSubstitute, especially a substitute teacherSubtitle, especially in connection with anime films, and as opposed to dubSubmissive (BDSM)Subwoofersubscript, is the HTML element used to format text as subscript.subeditorsubcontractor
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A .sub file is used with some videos to allow video playback programs to display subtitles on the screen as a video is played. It can also be used by some encoders to insert subtitles directly into the finished video.A .sub file can also be a part of CloneCD image files.
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The English prefix sub- first appeared in the Middle English period and seems to have been borrowed directly from Latin, although it previously existed in words borrowed from Old French. In Latin it was both a prefix and a preposition. Meanings found in English include:"under, beneath" (examples: subterranean, submarine)"subsidiary, secondary" (example: subplot)"almost, nearly" (example: subhuman)(a few usages) "similar to but smaller": submachine gun, subnotebook
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Noun
1. a large sandwich made of a long crusty roll split lengthwise and filled with meats and cheese (and tomato and onion and lettuce and condiments); different names are used in different sections of the United States
(synonym) bomber, grinder, hero, hero sandwich, hoagie, hoagy, Cuban sandwich, Italian sandwich, poor boy, submarine, submarine sandwich, torpedo, wedge, zep
(hypernym) sandwich
2. a submersible warship usually armed with torpedoes
(synonym) submarine, pigboat, U-boat
(hypernym) submersible, submersible warship
(hyponym) attack submarine
(part-meronym) conning tower
Verb
1. be a substitute; "The young teacher had to substitute for the sick colleague"; "The skim milk substitutes for cream--we are on a strict diet"
(synonym) substitute, stand in, fill in
(hypernym) exchange, change, interchange
(derivation) subbing, substituting

sub, subordinate, secondary, subdivision of

pref. sub, under, beneath, below