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true character; true form; true colors; identity; truth (of a mystery, phenomenon, etc.); origin
consciousness; one's senses
犯人の正体が明らかになった。
The criminal's true identity became clear.
彼の正体を知って驚きました。
I was surprised to know his true identity.
正体不明の物体が飛んでいる。
An object of unknown identity is flying.