Yes, limp is a Scrabble word!
...and is worth 8 points in Scrabble, and 11 points in Words with Friends
limp
Verb
1. Walk impeded by some physical limitation or injury
2. Proceed slowly or with difficulty
Adjective
1. Not firm
2. Lacking in strength or firmness or resilience
Noun
1. The uneven manner of walking that results from an injured leg
What Scrabble words can I make with the letters in limp?
3 Letter Words
2 Letter Words