Staff shortly seen in rainwear (3)
I believe the answer is:
mac
'staff shortly seen in rainwear' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe you can see an association between them that I can't see?
'staff shortly' is the wordplay.
'staff' becomes 'mace' (a mace is a ceremonial staff or stick).
'shortly' means to remove the last letter.
'mace' with its last letter removed is 'MAC'.
Can you help me to learn more?
(Other definitions for mac that I've seen before include "laptop?" , "Coat - computer" , "It may help you keep dry" , "A rainproof" , "PC" .)