Wow, a spiked sporty hairline! (6,4)
I believe the answer is:
widows peak
'hairline' is the definition.
The answer and definition can be both body parts as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'wow a spiked sporty' is the wordplay.
'sporty' indicates anagramming the letters.
'wow'+'a'+'spiked'='wowaspiked'
'wowaspiked' is an anagram of 'WIDOWS PEAK'.
Can you help me to learn more?
(Other definitions for widows peak that I've seen before include "V-shaped hairline" , "Barnet v remaining" .)