South American sex appeal envelops line dance (5)
I believe the answer is:
salsa
'dance' is the definition.
(I've seen this before)
'south american sex appeal envelops line' is the wordplay.
'south american' becomes 'sa'.
'sex appeal' becomes 'sa'.
'envelops' means one lot of letters goes inside another (I've seen this in other clues).
'line' becomes 'l'.
'sa'+'sa'='sasa'
'sasa' placed around 'l' is 'SALSA'.
(Other definitions for salsa that I've seen before include "Cuban dance music or spicy sauce" , "Chilli sauce" , "Steps" , "hot stuff" , "Saucy dance" .)