Letter embellishment (5)
I believe the answer is:
serif
'letter embellishment' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for serif that I've seen before include "Detail on some typefaces" , "stroke of the pen" , "Part of letter" , "Slight projection finishing off printed letter - puts fires out" , "One feature of text" .)