Header missed in tight draw (5)
I believe the answer is:
lotto
'draw' is the definition.
(I've seen this before)
'header missed in tight' is the wordplay.
'header missed in' means to remove the first letter.
'tight' becomes 'blotto' (synonyms).
'blotto' with its initial letter taken away is 'LOTTO'.
(Other definitions for lotto that I've seen before include "National game with large money prizes" , "Children's game similar to bingo" , "Venetian painter - gambling game" , "Prize draw" , "gamble" .)