revealer

noun
UK /rɪˈviːlə/
US /rɪˈviːlər/

A person or thing that shows something that was hidden.

The flashlight was a revealer of the toys under the bed.


OTHER MEANINGS

2. A thing that makes a secret known to people.

The letter was a revealer of the family's old secret.

3. A device or tool that opens something up so you can see inside.

The little revealer on the box let us peek at the gift.

4. A person who tells others something surprising.

Mia was the revealer of the big surprise party.