Inconstant /(?)/

In·con·stant

Inconstant

a.
  1. Not constant; not stable or uniform; subject to change of character, appearance, opinion, inclination, or purpose, etc.; not firm; unsteady; fickle; changeable; variable; -- said of persons or things; as, inconstant in love or friendship.
    While we, inquiring phantoms of a day, Inconstant as the shadows we survey!
    — Boyse.