Bit of body odour from the bottom, of course (7)
I believe the answer is:
humerus
'bit of body' is the definition.
The definition and answer can be both body parts as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'odour from the bottom of course' is the wordplay.
'odour' becomes 'hum' (something with a bad smell is 'humming').
'from the bottom' says the letters should be written backwards (in a down clue, letters come from the bottom).
'of course' becomes 'sure' (I've seen this before).
'sure' reversed gives 'erus'.
'hum'+'erus'='HUMERUS'
Can you help me to learn more?
(Other definitions for humerus that I've seen before include "Arm bone (that sounds comical)" , "Upper arm bone" , "Arm bone - the "funny bone"" , "Boneo of the upper arm" , "What's often thought funny" .)