pe‧cu‧li‧ar‧i‧ty plural peculiarities
something that is a feature of only one particular place, person, situation etc
The lack of a written constitution is a peculiarity of the British political system.
a strange or unusual habit, quality etc:
Margaret regarded her mother's peculiarities with a fond tolerance.
the quality of being strange or unfamiliar
She was well aware of the peculiarity of her own situation.