mid-15c., enprowment "profitable use, management of something for profit," from Anglo-French emprowement, from emprouwer "turn to profit" (see improve). Meaning "betterment; act of making better, amelioration" is from 1640s. Meaning "production of something better, something better (than something else)" is from 1712. Meaning "buildings, etc. on a piece of property" is from 1773. Related: Improvements.

"improvement of one's character, etc., by one's own efforts," 1745, from self- + improvement.

"improvement," 1590s, from better (v.) + -ment.

1868, "upturned part," from up (adv.) + turn (n.). Meaning "improvement" (especially in economics) is from 1930.

c. 1400, melioracioun, "improvement, act or process of making or becoming better," from Late Latin meliorationem (nominative melioratio) "a bettering, improvement," noun of action from past-participle stem of meliorare "to improve" (see meliorate). Meliorations in Scottish law were "improvements made by a tenant upon rented land."

early 13c., "betterment, improvement;" c. 1300, of persons, "correction, reformation," from Old French amendement "rectification, correction; advancement, improvement," from amender "to amend" (see amend). The sense expanded 17c. to include "correction of error in a legal process" (c. 1600) and "alteration of a writ or bill" to remove its faults (1690s).

mid-14c., in religious use, "a building up of the soul," from Old French edificacion "a building, construction; edification, good example," and directly from Latin aedificationem (nominative aedificatio) "construction, the process of building; a building, an edifice," in Late Latin "spiritual improvement," from past participle stem of aedificare "to build" (see edifice). Religious use is as translation of Greek oikodome in I Corinthians xiv. Meaning "mental improvement" is 1650s. Literal sense of "building" is rare in English, but Middle English bilding sometimes was used in religious writing to translate Latin aedificatio.

mid-15c., "amenable to discipline by instruction or improvement by teaching," from Medieval Latin disciplinabilis "docile." Meaning "subject or liable to discipline or correction" is from 1870, from discipline + -able.

"act of improvement requiring modest effort," 1872, from verbal phrase touch up "improve or finish (as a painting or drawing) with light strokes" (1715), from touch (v.) + up (adv.).

1963, in U.S. postal ZIP code, an acronym for Zone Improvement Plan, no doubt chosen with conscious echo of zip (v.1). Alternative post code is attested by 1967 in Australia.