Calling Veronica to slyly abandon Reggie at entrance (9)
I believe the answer is:
evocation
'calling' is the definition.
(thesaurus)
'veronica to slyly abandon reggie at entrance' is the wordplay.
I cannot quite understand how this works, but
'at' could be 'on' (location) and 'on' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for evocation that I've seen before include "A calling forth" , "A spell" .)