Show tip of nose and powder over (5)
I believe the answer is:
eclat
'show' is the definition.
(thesaurus)
'tip of nose and powder over' is the wordplay.
'tip of' indicates one should take the final letters.
'and' says to put letters next to each other.
'powder' becomes 'talc' (talcing is a kind of powdering).
'over' says the letters should be written in reverse.
The final letter of 'nose' is 'e'.
'talc' back-to-front is 'clat'.
'e'+'clat'='ECLAT'
(Other definitions for eclat that I've seen before include "Showy effect (Fr.)" , "Cleat (anag.)" , "Brilliance" , "Conspicuous success or distinction - in France" , "Universal approval" .)