noun
cog
kog
noun
1
A tooth on a gear wheel, or the wheel itself.
"One of the cogs had worn down and the machine kept jamming."
2
An unimportant, replaceable part of a much bigger system, especially used of a person.
"He felt like just another cog in the corporate machine."
"No single soldier saw the whole plan — each was a cog in the operation."
How to Use Cog
Learner’s notesIn plain EnglishLiterally a gear tooth; figuratively, a small, replaceable part of something much larger.
Common pairings
a cog in the machine
cog in the wheel
cogwheel
Word Forms
cogged past tense, cogged past tense, cogs plural, cogs plural, cogs plural, cogs singular, cogs singular
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One of the _____ had worn down and the machine kept jamming.
Etymology
From Middle English cogge, probably from Old Norse, related to a word for a lump or swelling — the sense of "gear tooth" likely comes from the tooth's rounded shape.