Old timer initially greeting play (7)
I believe the answer is:
othello
'play' is the definition.
(play by William Shakespeare)
'old timer initially greeting' is the wordplay.
'initially' suggests taking the first letters.
'greeting' becomes 'hello' (hello is a kind of greeting).
The first letters of 'old timer' is 'ot'.
'ot'+'hello'='OTHELLO'
(Other definitions for othello that I've seen before include "Shakespeare's general" , "player from Stratford" , "jealous husband" , "Shakespeare tragedy" , "Hello to Shakespeare's tragic hero" .)