Dog moves with pep (7)
I believe the answer is:
whippet
'dog' is the definition.
(whippet is a kind of dog)
'moves with pep' is the wordplay.
'moves' indicates an anagram.
'with'+'pep'='withpep'
'withpep' with letters rearranged gives 'WHIPPET'.
(Other definitions for whippet that I've seen before include "Greyhound relative" , "Fast runner" , "Small slender breed of dog like a greyhound" , "Dog bred for racing" , "Dog related to 9 down" .)