Yes, peanut is a Scrabble word!

Adjective

1. Of little importance or influence or power; of minor status

Noun

1. Underground pod of the peanut vine

2. Widely cultivated American plant cultivated in tropical and warm regions; showy yellow flowers on stalks that bend over to the soil so that seed pods ripen underground

3. A young child who is small for his age

4. Pod of the peanut vine containing usually 2 nuts or seeds; `groundnut' and `monkey nut' are British terms