Unit of the fleet? (3)
I believe the answer is:
bus
'unit of the fleet?' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'unit of the fleet?' is the wordplay.
'unit' becomes 'B' (B is an example).
'of the fleet?' becomes 'us' (I can't justify this - if you can you should believe this answer much more).
'b'+'us'='BUS'
Can you help me to learn more?
(Other definitions for bus that I've seen before include "Coach" , "Public service vehicle" , "Road vehicle able to carry many passengers" , "People carrier" , "Use transport" .)