1
[ adjective ] marked by erratic changeableness in affections or attachments

Synonyms

volatile

Examples

"fickle friends" "a flirt's volatile affections"

Related terms

inconstant

2
[ adjective ] liable to sudden unpredictable change

Examples

"erratic behavior" "fickle weather" "mercurial twists of temperament" "a quicksilver character, cool and willful at one moment, utterly fragile the next"

Related terms

changeable

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