Some lounge lizard’s girl (5)
I believe the answer is:
eliza
'girl' is the definition.
'some lounge lizard's' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'ELIZA' is hidden in the letters of 'lounge lizards'.
(Other definitions for eliza that I've seen before include "Female" , "Miss Doolittle/s first name" , "girl" , "- Doolittle (My Fair Lady)" , "Miss Doolittle" .)