subs. (vulgar).A colic; a grumbling pain in the bowels. Hence (American) TO BELLY ACHE = to grumble.
1552. HULOET. Disceased with BEALYE ACHE, or frealynge in the bealye.
1804. SOUTHEY, Letters (1856), I, 268. A supper so hearty that it gave him a sad BELLY-ACHE.
1881. New York Times, 18 Dec. [quoted in Notes and Queries, 6 S., v., 65.]. BELLYACHE. To grumble without good cause. Employés BELLYACHE at being overworked, or when they fancy themselves underfed, etc.