concealedbutton
nounUK /kənˈsiːld ˈbʌtən/
US /kənˈsiːld ˈbʌtən/
A button that is hidden so you cannot see it.
She opened the secret pocket by pressing the concealed button under the collar.
OTHER MEANINGS
2. A button on a device or screen that is not visible until activated or revealed.
The app hides advanced options behind a concealed button in the corner.
3. A hidden control used to trigger a secret mechanism or feature.
The bookshelf slid open when he pressed the concealed button in the wall panel.
4. A button sewn on the inside of a garment so it does not show on the outside.
The coat uses concealed buttons to keep the front looking clean and smooth.