Maybe American football star is desperate, initially chasing the odds (8)
I believe the answer is:
spheroid
'maybe american' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'football star is desperate initially chasing the odds' is the wordplay.
'football star' becomes 'hero' (I am not sure about this - if you are sure you should believe this answer much more).
'initially' indicates taking the first letters.
'chasing' is a charade indicator (letters next to each other) (some letters chase after others).
'the odds' becomes 'sp' (betting abbreviation for starting price).
The first letters of 'is desperate' is 'id'.
'hero'+'id'='heroid'
'heroid' put after 'sp' is 'SPHEROID'.
Can you help me to learn more?
(Other definitions for spheroid that I've seen before include "Kind of globe, not perfectly round" , "Almost the shape of a ball" , "Solid" , "Round shape" , "Almost-perfect-ball shape" .)