Sign of emotion predator conjured up (8)
I believe the answer is:
teardrop
'sign of emotion' is the definition.
'predator conjured up' is the wordplay.
'conjured up' indicates an anagram (I've seen 'conjuring up' mean this).
'predator' with letters rearranged gives 'TEARDROP'.
(Other definitions for teardrop that I've seen before include "Secretion from lachrymal gland" , "A single globule of eye moisture" , "One shed from eye" , "Visible result of crying" , "Parroted (anag.)" .)