Excited zeal under hot girl (5)
I believe the answer is:
hazel
'girl' is the definition.
(girl's name)
'excited zeal under hot' is the wordplay.
'excited' indicates anagramming the letters.
'under' means one lot of letters go next to another.
'hot' becomes 'h' (abbreviation eg on taps).
'zeal' is an anagram of 'azel'.
'azel' after 'h' is 'HAZEL'.
(Other definitions for hazel that I've seen before include "Tree - greenish-brown" , "Tree of the birch family" , "Shrub called the cob, which yields nuts" , "Catkin-bearing tree" , "wood" .)