The definition of a cog is any of the teeth on a wheel or gear that fits into an opposite notch to cause motion of the wheel, or a person who is important but not critical in the structure of an organization.(noun)
An example of a cog is the points on a bike gear that fit into the bike chain in order to move the bike forward.
See cog in Webster's New World College Dictionary
Origin: ME cog, cogge < ? Scand, as in Norw kug, Swed kugge, a cog, tooth < IE *gugā a hump, ball < base *gēu-, to bend, arch > OE cycgel, cudgel
See cog in American Heritage Dictionary 4
Origin: Middle English cogge
Origin: , probably of Scandinavian origin
Origin: ; akin to Swedish kugg, kugge.
verb cogged cogged, cog·ging, cogs verb, transitive
Origin: Origin unknown.
Origin: Alteration (influenced by cog1)
Origin: of cock, to join with tenons.
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