"aged (some number of years)," abbreviation of Latin aetatis "of the age of," genitive singular of aetas "age" (see age (n.)). "Chiefly used in classic or scholarly epitaphs or obituaries" [Century Dictionary].

"old age, especially the weakness or imbecility due to old age," 1753, from senile + -ity.

"former ages, old times," c. 1400, poetic or archaic form of old; in some cases from Old English eald, yldu, yldo "old age; an age; age as a period of life."

late 14c., "childhood, minority, state of not being of age, period of legal infancy," from Anglo-French nounage (early 14c.), Old French nonaage, from non- (see non-) + age (see age (n.)). Figurative use from 1580s.

c. 1400, from Anglo-French thaynage (c. 1300), from English thane + Old French suffix -age (see -age).

1660s, "suited to or characteristic of old age," from French sénile (16c.), from Latin senilis "of old age," from senex (genitive senis) "old, old man" (from PIE root *sen- "old"). The meaning "infirm from age; pertaining to or proceeding from the weakness that usually attends old age" is attested by 1882; senile dementia is attested by 1851.

"old age, decrepitude; great age, antiquity; the state of being old," Old English ealdnysse; see old + -ness.

1823, "anecdotes collectively," from anecdote + -age. As a jocular coinage meaning "garrulous old age" it is recorded from 1835, and spawned anecdotard (1894).

"having the same age, having lived for an equal period," 1620s, from Late Latin coaevus"of the same age," from assimilated form of Latin com "with, together" (see com-) + aevum "an age" (from PIE root *aiw- "vital force, life; long life, eternity"). As a noun from c. 1600.

1893, from weight (n.) + -age.