Short period of enchantment (5)
I believe the answer is:
spell
I believe this clue is a double definition.
'short period' is the first definition.
(I've seen this in another clue)
'enchantment' is the second definition.
(I know that enchantment can be written as spell)
'of' acts as a link.
(Other definitions for spell that I've seen before include "Incantation; write in letters" , "Incantation; splinter of wood" , "... mean" , "Fascination" , "influence" .)