c. 1400, exempten, "to relieve, to free or permit to be free" (from some requirement or condition, usually undesirable), from Anglo-French exempter, from exempt (adj.); see exempt (adj.). Related: Exempted; exempting.
mid-15c., "bound or obliged by law," probably from Anglo-French *liable, from Old French lier "to bind, tie up, fasten, tether; bind by obligation" (12c.), from Latin ligare "to bind, to tie" (from PIE root *leig- "to tie, bind"). With -able. Perhaps from an unattested word in Old French or Medieval Latin. General sense of "exposed to" (something undesirable) is from 1590s. Incorrect use for "likely" is attested by 1850.
1560s, "that which purges," from purge (v.). Meaning "a purgative, an act of purging" is from 1590s. Political or social sense of "removal (from a governing body, party, army, etc.) of persons deemed undesirable" is by 1730 (in reference to Pride's Purge); modern use in reference to the Soviet Union is by 1933. The earliest sense of the word in English was "examination or interrogation in a legal court" (mid-15c.), a sense now obsolete even if the feeling persists.
c. 1400, exempcioun, "immunity from a law or statute, state of being free from some undesirable requirement," from Old French exemption, exencion or directly from Latin exemptionem (nominative exemptio) "a taking out, removing," noun of action from past-participle stem of eximere "remove, take out, take away; free, release, deliver, make an exception of," from ex "out" (see ex-) + emere "buy," originally "take," from PIE root *em- "to take, distribute."
1560s, "to thrust out, remove, throw out of doors," from Latin eliminatus, past participle of eliminare "thrust out of doors, expel," from ex limine "off the threshold," from ex "off, out" (see ex-) + limine, ablative of limen "threshold" (see limit (n.)).
Used literally at first; the sense of "exclude, throw aside, or disregard as undesirable or unnecessary" is attested by 1714; the sense of "expel waste from the body" is by c. 1795. Related: Eliminated; eliminating; eliminative; eliminatory.
U.S. slang; said in "Dictionary of American Slang" to be originally 1920s army and 1930s college student slang for "venereal disease." Thus by 1940, "dirty, disreputable person," and by 1950, "undesirable impurity." By 1945 (with various modifiers) it was the G.I.'s name for disease of any and every sort."
Perhaps this word is a continuation of crud as the old metathesis variant of curd (q.v.), which would make it an unconscious return to the original Middle English form of that word. Century Dictionary (1897) has crud only in the sense "Obsolete or dialectal form of curd."