Ch 21

knoll- a small, rounded hill or eminence; hillock. tattoo- a signal on a drum, bugle, or trumpet at night, for soldiers or sailors to go to their quarters. cuirass- defensive armor for the torso comprising a breastplate and backplate, originally made of leather.halberd- a shafted weapon with an axlike cutting blade, beak, and apical spike, used especially in the 15th and 16th centuries. reserve- to serve again.placid- pleasantly calm or peaceful; unruffled; tranquil; serenely quiet or undisturbed.