c. 1300, suowne, suun, "state of unconsciousness," probably from Old English geswogen "in a faint," past participle of a lost verb *swogan (see swoon (v.)).
c. 1200, "to become unconscious," probably from a lost Old English verb *swogan (as in Old English aswogan "to choke"), of uncertain origin. Compare Low German swogen "to sigh." Related: Swooned; swooning.
1530s, "contraction of a word by omission of middle sounds," from Medieval Latin syncopationem (nominative syncopatio) "a shortening or contraction," from past participle stem of syncopare "to shorten," also "to faint away, to swoon," from Late Latin syncope (see syncope). Musical sense is attested from 1590s.
c. 1600, "shorten words by omitting syllables or letters in the middle," back-formation from syncopation, or else from Late Latin syncopatus, past participle of syncopare "to shorten," also "to faint away, to swoon," from Late Latin syncope (see syncope). Musical sense is from 1660s. Related: Syncopated; syncopating.
c. 1300, "grow weak, become enfeebled," also "lack courage or spirit, be faint-hearted," and "to pretend, feign;" from faint (adj.). Sense of "swoon, lose consciousness" is from c. 1400. Also used in Middle English of the fading of colors, flowers, etc. Related: Fainted; fainting. For Chaucer and Shakespeare, also a transitive verb ("It faints me").