Instruction to secretary: ____ mea verba; to a poet ____ (compone) versus (6)
I believe the answer is:
scribe
'instruction' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for scribe that I've seen before include "7 down teacher of the Jewish Law" , "Clerk, a public copyist" , "Writer of other days" , "A writer of old" , "Scholar of Jewish law" .)