独ひとりよがり

noun, na-adjective, noun which may take the genitive case particle 'no'

self-righteous; smug; self-satisfied; complacent

Describes a person who is convinced of their own correctness or superiority, often ignoring others' opinions. Can be used as a noun or adjectivally (な-adjective or の-adjective).

• 彼かれの独ひとりよがりな態たい度どにはうんざりだ。

  I'm fed up with his self-righteous attitude.

• 独ひとりよがりの考かんがえ方かたでは、チームでうまくやっていけない。

  With a self-centered way of thinking, you can't get along well in a team.