break-vow

From break +‎ vow.

break-vow (plural break-vows)

1. (obsolete, derogatory) An untrustworthy person; someone who habitually breaks vows and promises.
   • c. 1596 (date written), William Shakespeare, “The Life and Death of King Iohn”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act II, scene i]:

     With that same purpose-changer, that sly devil, / That broker, that still breaks the pate of faith, / That daily break-vow, he that wins of all, / Of kings, of beggars, old men, young men, maids,

• break-promise, oathbreaker, piker (Australia & New Zealand, slang), reneger