Green’s Dictionary of Slang

(US black) to talk, thus jaw-blocking, a chat, a conversation.

1946		Mezzrow & Wolfe Really the Blues 24: I used to see Scarface around there and jawblock with him sometimes.
1957		W. Brown Wicked Streets (2025) 22: ‘Just a little chat, Diane. Just some jaw-blocking is all’.
1959		W. Brown Teen-Age Mafia 59: He’d met with a couple of Daggers and they’d got to jaw-blocking.