na-adjective
frightening; fearsome; awful
Describes a look, atmosphere, or manner that seems frightening or dreadful. Often used in literary or descriptive contexts.
彼は恐ろしげな顔でこちらをにらんだ。
He glared at me with a frightening look on his face.
その森は夜になると恐ろしげな雰囲気に包まれる。
At night, the forest is enveloped in a fearsome atmosphere.