Student extremely anxious over labelling for vinaigrette, perhaps (5,8)
I believe the answer is:
salad dressing
'vinaigrette perhaps' is the definition.
(vinaigrette is a kind of salad dressing)
'student extremely anxious over labelling' is the wordplay.
'student' becomes 'l' (as in L-plates for learner drivers).
'extremely' says to hollow out the word (remove centre letters) (only the extremes of the word are used).
'over' says the letters should be written in reverse.
'labelling' becomes 'addressing' (addressing can mean adding an address label).
'anxious' with its middle taken out is 'as'.
'l'+'as'='las'
'las' back-to-front is 'sal'.
'sal'+'addressing'='SALAD-DRESSING'
'for' acts as a link.
(Other definitions for salad dressing that I've seen before include "leaves having taken this coat?" , "Mayonnaise, e.g." , "Vinaigrette or mayonnaise, for example" , "saucy thing!" , "Eg, Thousand Island or French" .)