unintendedknock
nounUK /ˌʌnɪnˈtɛndɪd nɒk/
US /ˌʌnɪnˈtɛndɪd nɑːk/
A knock you did not mean to make.
The unintendedknock on the door woke the baby.
OTHER MEANINGS
2. A hit that happens by accident.
His unintendedknock sent the cup rolling off the table.
3. A small sound made without planning.
An unintendedknock echoed when she brushed the wall.
4. A mistake caused by hitting something softly.
The unintendedknock on the glass left a tiny mark.