seriously

adverb

1. in a serious manner: He shook his head seriously.
2. to an alarmingly grave extent: seriously ill.
3. with genuine, earnest intent; sincerely: Seriously, kids, we have to get home before dark.

adverb

1. in a serious manner or to a serious degree
2. informal extremely or remarkablyseriously tall

adv.c.1500, from serious + -ly (2). To take (something) seriously is from 1782.