In short, a bicycle and a half? (5)
I believe the answer is:
trike
'in short' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps there's a link between them I don't understand?
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for trike that I've seen before include "Tricycle (inf.)" , "Three-wheeled vehicle" , "Three-wheeled cycle" , "transport system" , "Three-wheeler" .)