After-shave is a terrible strain on a fellow (10)
I believe the answer is:
astringent
'after-shave' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'terrible strain on a fellow' is the wordplay.
'terrible' indicates anagramming the letters.
'on' says to put letters next to each other.
'a fellow' becomes 'gent' (synonyms).
'strain' anagrammed gives 'astrin'.
'astrin'+'gent'='ASTRINGENT'
'is a' is the link.
Can you help me to learn more?
(Other definitions for astringent that I've seen before include "description of wine?" , "Lotion" , "(Of taste) sharp, bitter" , "(Medication) causing contraction - stern giant (anag)" , "Styptic" .)