apiece

As a verb apair

is to impair or become impaired; to injure.

As an adverb apiece is

each by itself; by the single one; to each; as the share of each.

Apiece is a synonym of each.

As an adverb apiece

is each by itself; by the single one; to each; as the share of each.

As a determiner each is

all; every;.

As a noun each is

(operations|philosophy) an individual item: the least quantitative unit in a grouping.

Apiece is a synonym of respectively.

As adverbs the difference between apiece and respectively

is that apiece is each by itself; by the single one; to each; as the share of each while respectively is in a relative manner; often used when comparing lists, where the term denotes that the items in the lists correspond to each other in the order they are given.

As adverbs the difference between apiece and individually

is that apiece is each by itself; by the single one; to each; as the share of each while individually is as individuals, separately, independently.

As adverbs the difference between apiece and aside

is that apiece is each by itself; by the single one; to each; as the share of each while aside is to or on one side so as to be out of the way.

As a noun aside is

an incidental remark made quietly so as to be heard by the person to whom it is said and not by any others in the vicinity.

As a noun piece

is a part of a larger whole, usually in such a form that it is able to be separated from other parts.

As a verb piece

is to assemble (something real or figurative).

As an adverb apiece is

each by itself; by the single one; to each; as the share of each.