Creative heart is ticking somewhat (8)
I believe the answer is:
artistic
'creative' is the definition.
(I've seen this before)
'heart is ticking somewhat' is the wordplay.
'somewhat' indicates a hidden word.
'ARTISTIC' can be found hidden inside 'heart is ticking'.
(Other definitions for artistic that I've seen before include "Having a creative imagination" , "Aesthetically pleasing" , "Aesthetic, creative" , "in an aesthetic way" , "Having creative gifts" .)