basalt

n [U] type of dark rock of volcanic origin 玄武岩.

barracks, barracuda, barrage, barrel, barrel-organ, barren, barrenness, barricade, barrier, barrier cream, barrier reef, barring, barrio, barrister, barrow, barrow boy, Bart, bartender, barter, bas-relief, base, base on (upon), base rate, baseball, baseboard, based on, baseless, baseline, basely, basement, baseness, bases, bash, bashful, bashfully, bashfulness, bashing, basic, BASIC (also Basic), basic slag,