acidulus

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.

ăcĭdŭlus, a, um, adj., dim. [acidus],

a little sour , sourish , acidulous : sapor, Plin. 15, 15, 16, § 54: aqua, mineral water , id. 2, 103, 106, § 230; 31, 2, 5, § 9; so, fons, ib.