Resin extract largely employed making ink initially (5)
I believe the answer is:
elemi
'resin' is the definition.
(I know that elemi is a type of gum resin)
'extract largely employed making ink initially' is the wordplay.
'initially' suggests taking the first letters.
The initial letters of 'extract largely employed making ink' is 'ELEMI'.
(Other definitions for elemi that I've seen before include "aromatic resin" , "Oleoresin" , "Extract" , "It's fragrance" , "Fragrant tree resin used as incense - I'm Lee (anag)" .)