Perform the tango with a girl (3)
I believe the answer is:
dot
'girl' is the definition.
'perform the tango' is the wordplay.
'perform' becomes 'do' (both can mean complete an action).
'the tango' becomes 'T' (phonetic alphabet: alpha, bravo, charlie etc.).
'do'+'t'='DOT'
'with a' acts as a link.
(Other definitions for dot that I've seen before include "Long-ago year?" , "Cotton, say" , "Speck or period" , "Small round spot" , "Internet punctuation mark" .)