страшно

Adverb

 * 1) scarily, frightfully
 * 2) terribly, dreadfully
 * 3)  very, extremely

Adverb

 * 1) terrifyingly
 * 2) very, badly

Predicative

 * 1) it is frightful, it is terrifying, one is scared

Adverb

 * 1) terribly, awfully, horribly

Etymology
From.

Adverb

 * 1) terrifyingly, terribly, awfully, horribly

Predicative

 * 1) (it is) frightful, terrifying, dreadful, (one is) frightened, scared