A cross tops empty talismans (7)
I believe the answer is:
amulets
'talismans' is the definition.
('amulet' can be a synonym of 'talisman')
'a cross tops empty' is the wordplay.
'cross' becomes 'mule' (a mule is a cross of a donkey and a horse).
'empty' says to hollow out the word (remove centre letters).
'tops' with its middle taken out is 'ts'.
'a'+'mule'+'ts'='AMULETS'
(Other definitions for amulets that I've seen before include "Lucky charms" , "Ornaments worn as charms against evil" .)