Least  —adj. 1 smallest, slightest. 2 (of a species etc.) Very small. —n. The least amount. —adv. In the least degree.  at least 1 at any rate. 2 (also at the least) not less than. In the least (or the least) (usu. With neg.) At all (not in the least offended). To say the least putting the case moderately. [old english, superlative of *less]