Finger or toe (5)
I believe the answer is:
This clue is a double definition.
'finger' is the first definition.
(I know that finger can be written as digit)
'toe' is the second definition.
(digit on a foot)
(Other definitions for digit that I've seen before include "Need a bit of a hand" , "Finger; number" , "Single figure - finger" , "a number less than ten" , "A character" .)