a calculator that keeps a record of the number of times something happens

a return punch (especially by a boxer)

a piece of leather forming the back of a shoe or boot

(computer science) a register whose contents go through a regular series of states (usually states indicating consecutive integers)

a quick reply to a question or remark (especially a witty or critical one)

a person who counts things

to do something to avoid or decrease the harmful or unpleasant effects of something