stock-still
adjectiveUK /ˌstɒk ˈstɪl/
US /ˌstɑːk ˈstɪl/
Not moving at all.
The rabbit stood stock-still when it saw the fox.
RELATED WORDS
OTHER MEANINGS
2. Completely quiet and without any movement.
The whole room went stock-still when the teacher walked in.
3. Standing so still that it seems like a statue.
The guard stayed stock-still at the gate for hours.
4. Not changing position even a tiny bit.
She held the puppy stock-still while the vet checked its ears.