5 across
Workman
is
good
but
not
so
hard-working
(7)
Workman is good but not so hard-working (7)
hints
0
checks
0
hints
The definition is at the beginning of the clue.
How the clue works
Workman is your definition — a tradesman, specifically one who fits glass. Then the wordplay builds it up: G (the standard abbreviation for good) placed in front of LAZIER (not so hard-working), and there's your answer.