D defs.my
Entry 2 senses Webster, 1913

Flighty

/flīt'-ē/ · Flight·y · IPA /ˈflaɪti/
01 a. Fleeting; swift; transient.
  1. 1.
    Fleeting; swift; transient.
    “The flighty purpose never is o'ertook, Unless the deed go with it.” Shak.
  2. 2.
    Indulging in flights, or wild and unrestrained sallies, of imagination, humor, caprice, etc.; given to disordered fancies and extravagant conduct; volatile; giddy; eccentric; slighty delirious.
    “Proofs of my flighty and paradoxical turn of mind.” Coleridge.
    “A harsh disciplinarian and a flighty enthusiast.” — J. S. Harford.