Present suppliers almost great (4)
I believe the answer is:
magi
'present suppliers' is the definition.
(I've seen this before)
'almost great' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'great' becomes 'magic' (both can mean very good).
'magic' with its final letter removed is 'MAGI'.
(Other definitions for magi that I've seen before include "Persian wise men" , "Star witnesses" , "Wise men who were guided by a star" , "present suppliers" , "Travellers in NT" .)