In*con"stant (?), a. [L. inconstans: cf. F. inconstant. See In- not, and Constant.] 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. "The inconstant moon." Shak.

While we, inquiring phantoms of a day,
Inconstant as the shadows we survey!

Syn. -- Mutable; fickle; volatile; unsteady; unstable; changeable; variable; wavering; fluctuating.