I
In military science, the preparation of soldiers for performance of their duties through the practice of prescribed movements.
It trains soldiers in battle formations, familiarizes them with their weapons, and develops a sense of teamwork and discipline. Today close-order drill is used for marching, ceremonies, and parades; combat drill is used to practice the looser routines of battle. It was introduced by the Greeks, who practiced the maneuvers of the phalanx . Careful training of the Gustav II Adolf of Sweden led in reintroducing drill techniques in early 17th-century Europe.
II
Large, short-tailed monkey ( Mandrillus leucophaeus , family Cercopithecidae).
Formerly found from Nigeria to Cameroon, it is now restricted to remote forest regions of Cameroon because of hunting and deforestation. Like the related mandrill , the drill is stout-bodied and has vividly coloured buttocks. The male is about 32 in. (82 cm) long and has a black face. Its lower lip is bright red, the hairs around the face and a tuft behind the ears are yellowish white, and the rest of the fur is olive-brown. An omnivore, it is mainly terrestrial, gregarious, and powerful, and it can fight ferociously if molested.
Drill ( Mandrillus leucophaeus ).
J. Kohler/Bavaria-Verlag
III
Tool to make holes, usually by revolving.
Drills, gimlets, and augers have cutting edges that detach material to leave a hole. Drilling usually requires high speed and low {{link=torque">torque , with little material being removed during each revolution of the tool. The earliest (perhaps Bronze Age ) drill points had sharp edges that ultimately developed into arrow shapes with two distinct cutting edges. This shape was effective and remained popular until the late 19th century, when factory-made, spiral-fluted twist drills became available at reasonable cost to displace the blacksmith-made articles. Rotating drill bits containing diamonds or other hard materials are used for drilling rock, as for tunnels or oil wells. See also drill press .