"improvement of one's character, etc., by one's own efforts," 1745, from self- + improvement.
Entries linking to self-improvement
self-
word forming element indicating "oneself," also "automatic," from Old English use of self (pron.) in compounds, such as selfbana "suicide," selflice "self-love, pride, vanity, egotism," selfwill "free will." Middle English had self-witte "one's own knowledge and intelligence" (early 15c.).
OED counts 13 such compounds in Old English. Middle English Compendium lists four, counting the self-will group as a whole. It re-emerges as a living word-forming element mid-16c., "probably to a great extent by imitation or reminiscence of Greek compounds in (auto-)," and formed a great many words in the pamphlet disputes of the 17c.
improvement n.
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.