Epigram slotted into essay, ingeniously (6)
I believe the answer is:
saying
'epigram' is the definition.
(I've seen this before)
'into essay ingeniously' is the wordplay.
'into' indicates a hidden word.
'SAYING' is hidden within 'essay ingeniously'.
'slotted' is the link.
This may not be correct. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for saying that I've seen before include "Expressing in words" , "Motto" , "Speaking; adage" , "Saw" , "Adage, maxim" .)