Etymology
Advertisement
fickle (adj.)
c. 1200, "false, treacherous, deceptive, deceitful, crafty" (obsolete), probably from Old English ficol "deceitful, cunning, tricky," related to befician "deceive," and to facen "deceit, treachery; blemish, fault." Common Germanic (compare Old Saxon fekan "deceit," Old High German feihhan "deceit, fraud, treachery"), from the same source as foe.

Sense of "changeable, inconstant, unstable" is from c. 1300 (especially of Fortune and women). Related: Fickleness. Fickly (c. 1300) is rare or obsolete. Also with a verb form in Middle English, fikelen "to deceive, flatter," later "to puzzle, perplex," which survived long enough in Northern dialects to get into Scott's novels. Fikel-tonge (late 14c.) was an allegorical or character name for "one who speaks falsehoods."
Related entries & more 
Advertisement
variable (adj.)
late 14c., of persons, "apt to change, fickle," from Old French variable "various, changeable, fickle," from Late Latin variabilis "changeable," from variare "to change" (see vary). Of weather, seasons, etc., attested from late 15c.; of stars, from 1788.
Related entries & more 
inconstant (adj.)
c. 1400, "fickle, not steadfast," from Old French inconstant "variable, eccentric" (14c.), from Latin inconstantem (nominative inconstans) "changeable, fickle, capricious," from in- "not, opposite of, without" (see in- (1)) + constantem (see constant). Related: Inconstantly.
Related entries & more 
changeful (adj.)

"inconstant, fickle," c. 1600, from change (n.) + -ful. Related: Changefulness.

Related entries & more 
capricious (adj.)
1590s, "humorous;" c. 1600, "apt to change the mind suddenly, fickle," from French capricieux "whimsical" (16c.), from Italian capriccioso, from capriccio (see caprice). Related: Capriciously; capriciousness.
Related entries & more 
Advertisement
flighty (adj.)
1550s, "swift," from flight (n.1) + -y (2). Sense of "fickle or frivolous" is from 1768, perhaps from notion of "given to 'flights' of imagination." Related: Flightiness.
Related entries & more 
instable (adj.)
c. 1400, from Latin instabilis "unsteady, not firm, inconstant, fickle," from in- "not, opposite of" (see in- (1)) + stabilis (see stable (adj.)). Now mostly replaced by unstable.
Related entries & more 
fleeting (adj.)
early 13c., "fickle, shifting, unstable," from Old English fleotende "floating, drifting," later "flying, moving swiftly," from present participle of fleotan "to float, drift, flow" (see fleet (v.)). Meaning "existing only briefly" is from 1560s. Related: Fleetingly.
Related entries & more 
whirligig (n.)
mid-15c., a child's toy, from whirl (v.) + gig (see gig (n.1)). Meaning "anything in constant motion" is from 1580s; "fickle, flighty person" is from c. 1600; as a type of water beetle, from 1713.
Related entries & more 
instability (n.)
early 15c., from Old French instabilité "inconstancy" (15c.) or directly from Latin instabilitatem (nominative instabilitas) "unsteadiness," from instabilis "unsteady, not firm, inconstant, fickle," from in- "not, opposite of" (see in- (1)) + stabilis (see stable (adj.)).
Related entries & more