To an extent, centaur uses constellation (6)
I believe the answer is:
taurus
'constellation' is the definition.
(Taurus is an example)
'to an extent centaur uses' is the wordplay.
'to an extent' indicates a hidden word (I've seen 'extent of' mean this (I've seen this in other clues)).
'TAURUS' can be found hidden inside 'centaur uses'.
(Other definitions for taurus that I've seen before include "Second sign of the zodiac, the Bull" , "Mountains in 8 across" , "Zodiacal bull" , "house" , "Bull star sign" .)