Start of beard - with subtle changes (7)
I believe the answer is:
stubble
'start of beard with subtle changes' is the definition.
I can't judge whether this definition defines the answer.
'start of beard with subtle changes' is the wordplay.
'start of' says to take the initial letters.
'with' means one lot of letters go next to another.
'changes' indicates anagramming the letters.
The first letter of 'beard' is 'b'.
'b' after 'subtle' is 'subtleb'.
'subtleb' is an anagram of 'STUBBLE'.
(Other definitions for stubble that I've seen before include "Stalks left by harvester" , "Post-harvest stalks" , "Early growth of beard" , "Short whiskers" , "Cut stalks left in field" .)