Thick hair concealed by youth at chippie (6)
I believe the answer is:
thatch
'thick hair' is the definition.
(I've seen this before)
'concealed by youth at chippie' is the wordplay.
'concealed' indicates a hidden word.
'THATCH' is hidden within 'by youth at chippie'.
(Other definitions for thatch that I've seen before include "Old-fashioned roofing material" , "An old-fashioned roof covering of straw, reeds etc" , "nothing of interest to thief wanting roof lead" , "Old-fashioned roof covering material" , "Old roofing material" .)