- aberration
- abnormality
- aroma
- attribute
- badge
- boutade
- brainstorm
- brand
- cachet
- caprice
- cast
- character
- characteristic
- conceit
- configuration
- crank
- craze
- crotchet
- cut
- deformity
- deviation
- differentia
- eccentricity
- fad
- fancy
- fantastic notion
- fantasy
- feature
- figure
- flavor
- flimflam
- fool notion
- freak
- freakish inspiration
- gust
- habit
- hallmark
- harebrained idea
- humor
- idiocrasy
- idiosyncrasy
- impress
- impression
- index
- individualism
- irregularity
- kink
- lineaments
- maggot
- malformation
- mannerism
- mark
- megrim
- mold
- monstrosity
- nature
- notion
- oddity
- odor
- particularity
- passing fancy
- peculiarity
- property
- quality
- quip
- quirk
- seal
- shape
- singularity
- smack
- specialty
- stamp
- taint
- taste
- teratism
- token
- trick
- trick of behavior
- twist
- vagary
- whim
- whimsy
- whim-wham