Incantation (5)
There are a few possibilities for this:
open sesame
'incantation' is the definition.
(I know that incantation can be written as spell)
This is all the clue.
(Other definitions for spell that I've seen before include "Short period of time; incantation" , "JP" , "Period; piece of magic" , "Charm; short period" , "Stretch" .)
'incantation' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for chant that I've seen before include "Intone (psalm)" , "Incantatory song" , "Recite singingly" , "Mantra" , "Type of singing with a simple melody and several words sung on one note" .)
'incantation' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for open sesame that I've seen before include "Spell unlocking doors" , "a very successful means of achieving a result" , "Spell from Ali Baba and the Forty Thieves" , "Magical words" , "free entry" .)