What does the cryptic crossword clue "Writer returning only some of one's Biros (5)" mean?

The definition is "Writer". The wordplay uses a hidden word. Hidden reversed in "writer returning only some of oNE'S BIros" The answer is IBSEN.

Writer returning only some of one's Biros (5)

Times Cryptic #29213 | 14 Across | 2025-04-25 flower