Support, yes, but no backing (5)
I believe the answer is:
stool
This could be a double definition.
'support yes' is the first definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe there's a link between them I don't understand?
'no backing' is the second 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 don't see?
'but' acts as a link.
Can you help me to learn more?
(Other definitions for stool that I've seen before include "Seat without a back" , "Small seat" , "Armless seat" , "Backless chair" , "place butt on one?" .)