What does the cryptic crossword clue "Reddish brown, some of these pianos (5)" mean?

The definition is "Reddish". The wordplay uses a hidden word. Hidden in [the]SE PIA[nos]. The answer is SEPIA.

Reddish brown, some of these pianos (5)

Times Cryptic #29023 | 18 Across | 2024-09-16 flower