Idiosyncrasy

noun/id-ee-oh-sin-kruh-see/

Meaning

a mode of behavior or way of thought peculiar to an individual.

In context
One of his idiosyncrasies is eating dessert before the main course.

Remember it

Idio- means 'one's own' — an idiosyncrasy is your own quirky trademark habit.

Use it well

Use for harmless personal quirks: 'one of her idiosyncrasies is...'; gentler than 'weirdness'.