self-satisfaction (n.)

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.

early 14c., satisfaccioun, "performance by a penitent of an act set forth by a priest or other Church authority to atone for sin," from Old French satisfaction (12c.), from Latin satisfactionem (nominative satisfactio) "a satisfying of a creditor," noun of action from past-participle stem of satisfacere "discharge fully, comply with, make amends," literally "to do enough" (see satisfy).

Originally religious and involving such acts as expiatory prayer, self-denial, charity. The sense of "contentment, appeasement" is from late 14c. but was not common before 16c. The sense of "action of gratifying" (an appetite or desire) also is from late 14c.; that of "gratified or contented feeling or state of mind" is from late 15c. (Caxton).

From 1580s as "information that answers a person's demands or removes doubt." Hence the specific sense "opportunity of satisfying one's honor by accepting a duel, etc., with the aggrieved person" (c. 1600).