Less happy, having pelt used as means of promotion (10)
I believe the answer is:
stepladder
'means of promotion' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'less happy having pelt used' is the wordplay.
'less happy' becomes 'sadder' ('sad' can be the opposite of 'happy' so perhaps 'sadder' is reasonable for 'less happy').
'having' indicates putting letters inside.
'used' indicates an anagram.
'pelt' with letters rearranged gives 'tepl'.
'sadder' placed around 'tepl' is 'STEPLADDER'.
'as' is the link.
Can you help me to learn more?
(Other definitions for stepladder that I've seen before include "Portable means of ascent" , "Domestic climbing aid" , "Short folding climbing frame" , "Help for climber" , "Decorator's platform" .)