Scientist runs to stamina (9)
I believe the answer is:
anatomist
'scientist' is the definition.
The definition and answer can be both people as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'runs to stamina' is the wordplay.
'runs' indicates anagramming the letters.
'to'+'stamina'='tostamina'
'tostamina' is an anagram of 'ANATOMIST'.
Can you help me to learn more?
(Other definitions for anatomist that I've seen before include "One studying bodies" , "One studying bodily structure" , "Structural expert" , "Expert in the structure of human and animal bodies" , "Biological expert" .)