My prefix is quite definite.
My suffix lets you dream a bit.
My infix leaves it up to you.
In total, I am proved and true.
1 Answer
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My prefix is quite definite.
THE, definite article.
My suffix lets you dream a bit.
REM, sleep stage
My infix leaves it up to you.
OR, signifying choice
In total, I am proved and true.
THEOREM