Tough character to pull up stallion at the start (4)
I believe the answer is:
guts
'tough character' is the definition.
The answer and definition can be both human attributes as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'pull up stallion at the start' is the wordplay.
'pull' becomes 'tug' (to tug something is to pull it).
'up' shows that the letters should be reversed in order (in down clue: letters go upwards).
'at the start' says to take the initial letters.
The first letter of 'stallion' is 's'.
'tug' back-to-front is 'gut'.
'gut'+'s'='GUTS'
'to' is the link.
Can you help me to learn more?
(Other definitions for guts that I've seen before include "Spunk" , "Courage; entrails" , "Courage (coll.)" , "backbone" , "Cleans - bottle" .)