Printing unit with machine for printing female sovereign (7)
I believe the answer is:
empress
'female sovereign' is the definition.
(I've seen this before)
'printing unit with machine' is the wordplay.
'printing unit' becomes 'em' (in printing, unit of space as wide as a letter m).
'with' is a charade indicator (letters next to each other).
'machine' becomes 'press' (press is a kind of machine).
'em'+'press'='EMPRESS'
'for printing' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for empress that I've seen before include "Delilah?" , "Queen Victoria was one" , "one married to ruler?" , "Female sovereign" , "Josephine, for instance" .)