Artist supports Blades (7)
I believe the answer is:
rapiers
'blades' is the definition.
(rapier is a kind of blade)
'artist supports' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'supports' becomes 'piers' (pier is a kind of support).
'ra'+'piers'='RAPIERS'
(Other definitions for rapiers that I've seen before include "Double-edged swords" , "Straight swords with narrow blades" .)