plural of minute-jack

A figure which strikes the hour on the bell of some fanciful clocks; Jack o' the clock. / (obsolete) A timeserver; an inconstant person.

(US) A short-handled sledgehammer used with one hand, with a head weighing 3-4 pounds and two flat faces.

(US) A long-handled sledgehammer used with both hands

plural of single jack

plural of double jack

plural of Cousin Jack

(slang, dated) A Cornishman.

An arch of the thickness of one brick.

(UK) One of the shorter rafters used in constructing a hip or valley roof.