Delay sailors eating eats (9)
I believe the answer is:
tardiness
'delay' is the definition.
(I've seen this before)
'sailors eating eats' is the wordplay.
'sailors' becomes 'tars' (tar is a kind of sailor).
'eating' is an insertion indicator.
'eats' becomes 'dines' (dining is a kind of eating).
'tars' going around 'dines' is 'TARDINESS'.
(Other definitions for tardiness that I've seen before include "No quality in fast food" , "Delay" , "Becoming late" , "Being behind quality" , "being a little late" .)