coag

Webster's Dictionary (GCIDE)

Coag \Coag\, n. See Coak, a kind of tenon. [1913 Webster]

Coak \Coak\, n.

1.(Carp.) A kind of tenon connecting the face of a scarfed timber with the face of another timber, or a dowel or pin of hard wood or iron uniting timbers. [Also spelt coag.] [1913 Webster]

2.A metallic bushing or strengthening piece in the center of a wooden block sheave. [1913 Webster]