Defn: 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.

2. (Carp.) (a) A kind of tenon on the end of a joist, received into a notch in a bearing timber, and resting flush with its upper surface. (b) A tenon in a scarf joint; a coak. Knight.

3. (Mining.)

Defn: One of the rough pillars of stone or coal left to support the roof of a mine.

COG
Cog, v. t.

Defn: To furnish with a cog or cogs. Cogged breath sound
(Auscultation), a form of interrupted respiration, in which the
interruptions are very even, three or four to each inspiration.
Quain.

COG
Cog, n. Etym: [OE. cogge; cf. D. kog, Icel. kuggr Cf. Cock a boat.]

Defn: A small fishing boat. Ham. Nav. Encyc.

COGENCY
Co"gen*cy, n. Etym: [See Cogent.]

Defn: The quality of being cogent; power of compelling conviction; conclusiveness; force. An antecedent argument of extreme cogency. J. H. Newman.