peculiarity
noun
[ pɪˌkjuːlɪˈarɪti ]
• a strange or unusual feature or habit.
• "for all his peculiarities, she finds him quite endearing"
Similar:
oddity,
anomaly,
abnormality,
twist,
quirk,
eccentricity,
trick,
outlier,
edge case,
idiosyncrasy,
mannerism,
foible,
caprice,
whimsy,
singularity,