Mistakenly calls the operator for something to eat (7)
I believe the answer is:
scallop
'something to eat' is the definition.
(scallop is a kind of food)
'mistakenly calls the operator' is the wordplay.
'mistakenly' indicates an anagram.
'the operator' becomes 'op' (I can't justify this - if you can you should give a lot more credence to this answer).
'calls' with letters rearranged gives 'scall'.
'scall'+'op'='SCALLOP'
'for' is the link.
Can you help me to learn more?
(Other definitions for scallop that I've seen before include "Marine mollusc" , "Shellfish that's also plc" , "Shellfish - badge worn by pilgrims to Santiago de Compostela" , "Mollusc or lacy edge" , "Bivalve mollusc with fan-shaped shell" .)