closed book   (TTS Sound)

The closed_book has 1 Senses.

• closed book, mystery, secret, enigma
• 不思議, 怪事, 不可思議, 怪奇, ミステリー, 不可解, ミステリ, 神秘, 怪, なぞ, はっきりしないこと
• something that baffles understanding and cannot be explained; "how it got out is a mystery"; "it remains one of nature's secrets"
• 理解するすべがなく説明できないもの