Strange hound -- tail's wagging (10)
I believe the answer is:
outlandish
'strange' is the definition.
(synonyms)
'hound tail's wagging' is the wordplay.
'wagging' indicates an anagram (letters swing or wag around).
'hound'+'tails'='houndtails'
'houndtails' anagrammed gives 'OUTLANDISH'.
(Other definitions for outlandish that I've seen before include "Exotic" , "Lad shoutin' (anag)" , "Bizarre - hound's tail (anag)" .)