What does the cryptic crossword clue "Gather undoctored author lacks English (4)" mean?

The definition is "Gather". The wordplay uses a deletion. SUSS (deletion) = SUSS; definition: "Gather" The answer is SUSS.

Gather undoctored author lacks English (4)

Guardian Cryptic #28975 | 6 Across | 2023-01-24 flower