A tooth, cam, or catch for imparting or receiving motion, as on a gear wheel, or a lifter or wiper on a shaft; originally, a separate piece of wood set in a mortise in the face of a wheel
(Council of Governments) is a voluntary consortium of local government representatives, from contiguous communities, meeting on a regular basis, and formed to cooperate on common planning and solve common development problems of their area COGs can function as the RTPAs and MPOs in urbanized areas
If you describe someone as a cog in a machine or wheel, you mean that they are a small part of a large organization or group. Mr Lake was an important cog in the Republican campaign machine. An instance of cheating; a swindle. To join with tenons. cognate