What does the cryptic crossword clue "Lug instrument and books round room? (8)" mean?

The definition is "Lug". The wordplay uses a charade (building blocks). OT (synonym of "books") + O (synonym of "round") + SCOPE (synonym of "room?"); definition: "Lug instrument" The answer is OTOSCOPE.

Lug instrument and books round room? (8)

Telegraph #30195 | 20 Across | 2023-01-12 flower

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Times Cryptic #27487 (2019-10-21)