Antonyms: fecundity, prolificness, fertility.

barrier, n. obstruction, impediment, obstacle, hindrance, barricade.

barter, n. traffic, exchange, trade, business.--v. traffic,
trade, exchange.

base, a. debased, impure, spurious, alloyed, counterfeit; low-minded,
unworthy, ignoble, mean, servile, groveling; despicable, discreditable,
disgraceful, venal; plebeian, obscure, untitled, unhonored.

base, n. basis, bottom, foundation, groundwork; pedestal; plinth.

baseboard, n. mopboard, scrubboard.

baseborn, a. plebeian.

baseless, a. unfounded, groundless.

basement, n. cellar. Associated Word: area.

bashful, a. over-modest, diffident, coy, shamefaced, sheepish,
retiring.

bashfulness, n. modesty, diffidence, shyness, over-modesty.

basis, n. foundation.

bask, v. luxuriate, revel.