a. 易变的, 不定的, 反复无常的

[医] 不定的, 变易的, 不恒定的

[ adj ]
likely to change frequently often without apparent or cogent reason; variable
<adj.all>
inconstant affectionsan inconstant lover
swear not by...the inconstant moon

Inconstant \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! --Boyse.

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