Sub is short for submarine, subscription, substitute or a submarine sandwich.
(noun)To sub is to substitute, to use someone or something instead of the person or object normally used.
(verb)An example of sub is to put in a different player when a player gets injured.
See sub in Webster's New World College Dictionary
Origin: < L sub, under, below: see up
See sub in American Heritage Dictionary 4
Origin:
Origin: Middle English
Origin: , from Latin
Origin: , from sub, under; see upo in Indo-European roots
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