na-adjective, noun which may take the genitive case particle 'no', noun
straight to the point; point-blank; frank; direct
Describes a manner of speaking or acting that is blunt and without preamble. Often used with に as an adverb.
単刀直入に言うと、その計画は失敗だ。
To put it bluntly, that plan is a failure.
彼は単刀直入な質問をした。
He asked a direct question.