serious

adj

1. Without humor or expression of happiness; grave in manner or disposition.

   “deadly serious”

   “It was a surprise to see the captain, who had always seemed so serious, laugh so heartily.”

2. Important; weighty; not insignificant.

   “This is a serious problem. We'll need our best experts.”

3. Really intending what is said (or planned, etc); in earnest; not jocular or deceiving.

   “After all these years, we're finally getting serious attention.”

   “He says he wants to buy the team, but is he serious?”

4. Committed.

adv

1. (colloquial, dialectal, not-comparable)seriously, in a serious manner (most often heard in take or mean serious)

   “The only time I walk out on singin' is when there's muckin' about and youse don't take it serious.”