Sailor has empty day, being late (5)
I believe the answer is:
tardy
'late' is the definition.
('tardy' can be a synonym of 'late')
'sailor has empty day' is the wordplay.
'sailor' becomes 'tar' (tar is a kind of sailor).
'has' means one lot of letters go next to another.
'empty' says to hollow out the word (remove centre letters).
'day' with its middle removed is 'dy'.
'tar'+'dy'='TARDY'
'being' is the link.
(Other definitions for tardy that I've seen before include "Backward" , "Unpunctual" , "Rather late" , "Late - slow" , "Late, delayed" .)