A hundred and two sailors share the bill (2-4)
I believe the answer is:
co-star
'share the bill' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.
'a hundred and two sailors' is the wordplay.
'two sailors' can mean two substitutions for 'sailor'.
'a hundred' becomes 'C' (Roman numerals).
'and' is a charade indicator (letters next to each other).
'sailor' becomes 'os' (ordinary seaman).
'sailor' becomes 'tar' (tar can mean a sailor).
'c'+'os'+'tar'='CO-STAR'
Can you help me to learn more?
(Other definitions for co-star that I've seen before include "Performer meriting joint billing" , "Actor sharing top billing" , "Joint main actor" , "Be joint lead (in film, play, etc)" , "Performer of equal importance" .)