na-adjective, noun which may take the genitive case particle 'no'
Describes something or someone that is oddly different from the norm, often with a nuance of being strangely unique or unconventional. Can be used for people, behavior, atmosphere, or appearance.
彼の服装は一種異様で、周りの人からじろじろ見られていた。
His outfit was so peculiar that people around him were staring.
There was a strangely unique atmosphere in that room.