noun, verb, cogged, cog⋅ging.| 1. | (not in technical use) a gear tooth, formerly esp. one of hardwood or metal, fitted into a slot in a gearwheel of less durable material. |
| 2. | a cogwheel. |
| 3. | a person who plays a minor part in a large organization, activity, etc.: He's just a small cog in the financial department. |
| 4. | (of an electric motor) to move jerkily. |
| 5. | to roll or hammer (an ingot) into a bloom or slab. |
| 6. | slip a cog, to make a blunder; err: One of the clerks must have slipped a cog. |

noun, verb, cogged, cog⋅ging.| 1. | Carpentry. (in a cogged joint) the tongue in one timber, fitting into a corresponding slot in another. |
| 2. | Mining. a cluster of timber supports for a roof. Compare chock (def. 4). |
| 3. | Carpentry. to join with a cog. |