Maybe Leo Tolstoy briefly is confused with Lenin, a leader of Communists (13)
I believe the answer is:
constellation
'maybe leo' is the definition.
(Leo is a constellation)
'tolstoy briefly is confused with lenin a leader of communists' is the wordplay.
'briefly' means to remove the last letter.
'is confused with' indicates an anagram.
'leader of' says to take the initial letters.
The initial letter of 'communists' is 'c'.
'tolstoy' with its final letter removed is 'tolsto'.
'lenin'+'a'+'c'='leninac'
'tolsto' with its letters mixed up with 'leninac' makes 'CONSTELLATION'.
(Other definitions for constellation that I've seen before include "Client to salon (anag.)" , "Twenty-five across for instance" , "Group of stars" , "Twins, perhaps" , "E.g Orion, Andromeda" .)