expire

Here the subject is a span of time: years, a term, a grace period. The King James Bible of 1611 writes "when the thousand yeeres are expired," using be where modern English usually says have expired. This differs from the "no longer valid" meaning because nothing loses its legal force. A period simply runs out.

A last breath lies behind this meaning. Latin exspīrō joins ex- "out" with spīrō "breathe, be alive," so to expire is to breathe one's life out. The word belongs to elevated and clinical prose. Samuel Richardson's Clarissa (1748) closes a deathbed scene with "he expired," and medical writing reports that a patient expired in hospital. In everyday speech, die remains the plain choice.

The literal Latin sense, the one behind the meaning "to die": to breathe out. Its partner is inspire, and older physiology used the two as a matched pair. Gideon Harvey (1672) describes lungs "inspiring and expiring air." The verb can take an object or stand alone, and in John Dryden's Meleager and Atalanta a boar's "nostrils flames expire."

The transitive use is old. Shakespeare's Romeo and Juliet speaks of choosing to "expire the term / Of a despised life," which makes the ending something done rather than something that happens. Compare the intransitive "come to an end", where a period runs out on its own. In this sense, someone causes the ending.

Breath lent to things without lungs: Latin ex- "out" plus spīrō "breathe" lets the earth, a vent or a censer breathe out what it holds. Francis Bacon, in 1627, writes of "the expiring of cold out of the inward parts of the earth in winter," so even cold could be given off this way. The verb takes a direct object, the thing emitted, unlike the "exhale" meaning, where the breath is a body's own.