A look of palpable eroticism (4)
I believe the answer is:
leer
'a look' is the definition.
(leer is a kind of look)
'of palpable eroticism' is the wordplay.
'of' says the answer is hidden in the clue.
'LEER' can be found hidden inside 'palpable eroticism'.
(Other definitions for leer that I've seen before include "Lascivious gaze" , "Ogle, smirk" , "Stare suggestively" , "Give sly look" , "Look lasciviously at" .)