Yes, clop is a Scrabble word!
...and is worth 8 points in Scrabble, and 11 points in Words with Friends
clop
Verb
1. Make or move along with a sound as of a horse's hooves striking the ground
Noun
1. The sound of a horse's hoofs hitting on a hard surface
What Scrabble words can I make with the letters in clop?
3 Letter Words
2 Letter Words