ni ‧ ce ‧ ty /ˈnaɪsəti, ˈnaɪsɪti/ BrE AmE noun ( plural niceties )
1 . [countable usually plural] a small detail or point of difference, especially one that is usually considered to be part of the correct way of doing something:
social niceties
legal niceties
nicety of
the niceties of political diplomacy
2 . to a nicety formal exactly