Hopeful (8)
There are a few possibilities for this:
optimistic
'hopeful' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for aspiring that I've seen before include "Strongly desiring to achieve" , "Striving" , "Hoping" , "Ambitious, hopeful" , "Would-be" .)
'hopeful' is the definition.
(synonyms)
This is all the clue.
(Other definitions for aspirant that I've seen before include "Awannabee found in past rain" , "One with ambition" , "One seeking eg promotion" , "expressing high ambition?" , "Hopeful, wannabe" .)
'hopeful' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for sanguine that I've seen before include "Optimistic or ruddy" , "Confidently optimistic and cheerful" , "Cheerfully optimistic" , "Confident < , or > ruddy" , "Cheerful, confident and full of hope" .)
(Other definitions for optimistic that I've seen before include "Pollyannaish" , "Happy-go-lucky" , "Hopeful and confident" , "Cheerful" , "Looking on the bright side" .)