1520s, "to unload, disburden," a literal sense now obsolete; 1570s as "relieve (of a charge, blame, etc.) resting on one; clear of something that lies upon the character as an imputation," from Latin exoneratus, past participle of exonerare "remove a burden, discharge, unload," from ex "out, out of, off" (see ex-) + onerare "to unload; overload, oppress," from onus (genitive oneris) "burden" (see onus). Related: Exonerated; exonerating.
"act of exonerating or of discharging or freeing; state of being discharged or freed from an accusation, obligation, debt, etc.," 1630s, from Late Latin exonerationem (nominative exoneratio) "an unloading, lightening," noun of action from past-participle stem of exonerare "free from a burden" (see exonerate).
early 14c., "to exempt, exonerate, release, free (from an obligation)," from Old French deschargier "to unload, discharge" (12c., Modern French décharger), from Late Latin discarricare, from dis- "do the opposite of" (see dis-) + carricare "to load a wagon or cart," from Latin carrus "two-wheeled wagon" (see car).
Meaning "to fulfill, to perform (one's duties, etc.)" is from c. 1400. Sense of "dismiss from office or employment" is from c. 1400. Meaning "to unload, to free from, disburden" is late 14c. Of weapons, "send forth by propulsion," transitive, 1550s; "to fire off," intransitive, 1580s. Of a river, "to empty itself," c. 1600. The electrical sense is first attested 1748. Related: Discharged; discharging.
early 15c., "alleviate (a disease or its symptoms) without curing," from Medieval Latin palliatus, literally "cloaked," from past participle of Late Latin palliare "cover with a cloak, conceal," from Latin pallium "cloak" (see pall (n.)). Meaning "excuse or extenuate (an offense) by pleading or urging extenuating circumstances or favorable representations" is from 1630s. Related: Palliated; palliating; palliation.
Palliate and extenuate come at essentially the same idea through different figures : palliate is to cover in part as with a cloak; extenuate is to thin away or draw out to fineness. They both refer to the effort to make an offense seem less by bringing forward considerations tending to excuse; they never mean the effort to exonerate or exculpate completely. [Century Dictionary]
c. 1300, relēsen, "to withdraw, revoke (a decree, etc.), cancel, lift; remit," from Old French relaissier, relesser "to relinquish, quit, let go, leave behind, abandon, acquit," variant of relacher "release, relax," from Latin relaxare "loosen, stretch out" (from re- "back" (see re-) + laxare "loosen," from PIE root *sleg- "be slack, be languid"). Latin relaxare is the source also of Spanish relajar, Italian relassare, and English relax, and the uncle of relish.
Meaning "alleviate, ease" is mid-14c., as is sense of "set free from (duty, etc.); exonerate." From late 14c. as "grant remission, forgive; set free from imprisonment, military service, etc." Also "give up, relinquish, surrender." In law, c. 1400, "to grant a release of property." Of press reports, attested from 1904; of motion pictures from 1912; of music recordings from 1962. As a euphemism for "to dismiss, fire from a job" it is attested in American English since 1904. Related: Released; releasing.
mid-13c., "attempt to clear (someone) from blame, find excuses for," from Old French escuser (12c., Modern French excuser) "apologize, make excuses; pardon, exonerate," from Latin excusare "excuse, apologize, make an excuse for, plead as an excuse; release from a charge; decline, refuse, excuse the refusal of" (source also of Spanish excusar, Italian scusare), from ex "out, away" (see ex-) + causa "accusation, legal action" (see cause (n.)).
Sense of "forgive, pardon, accept another's plea of excuse" is from early 14c. Meaning "to obtain exemption or release from an obligation or duty; beg to be excused" is from mid-14c. in English, as is the sense "defend (someone or something) as right." Sense of "serve as justification for" is from 1530s. Related: Excused; excusing. Excuse me as a mild apology or statement of polite disagreement is from c. 1600.