MC met at Astors' spread (11)
I believe the answer is:
toastmaster
'mc' is the definition.
(thesaurus)
'met at astors' spread' is the wordplay.
'spread' is an anagram indicator.
'met'+'at'+'astors'='metatastors'
'metatastors' with letters rearranged gives 'TOASTMASTER'.
(Other definitions for toastmaster that I've seen before include "Announcer at a formal dinner" , "MC at formal dinner" , "Emcee at a banquet" , "Master of ceremonies at a banquet" , "One introducing" .)