Charm left out of a hairdo (6)
I believe the answer is:
amulet
'charm' is the definition.
(synonyms)
'left out of a hairdo' is the wordplay.
'left' becomes 'l' (common abbreviation).
'out of' is a deletion indicator.
'hairdo' becomes 'mullet' (mullet is a type of hairdo).
'a'+'mullet'='amullet'
'amullet' with 'l' taken out is 'AMULET'.
(Other definitions for amulet that I've seen before include "Ornament worn as a charm against evil" , "Mascot" , "Lucky charm, talisman" , "Trinket worn to protect one from evil" , "Charm, lucky token" .)