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1. A subordinate who performs an important but routine function
   "he was a small cog in a large machine"
    
2. Tooth on the rim of gear wheel
   - sprocket

1. Roll steel ingots
    
2. Join pieces of wood with cogs

Derived forms: cogged, cogs, cogging

Type of: foot soldier, join, roll, roll out, subordinate, subsidiary, tooth, underling, understrapper [informal]

Part of: cogwheel, gear, gear wheel, geared wheel

Encyclopedia: Cog