bottomrim
nounUK /ˈbɒtəm rɪm/
US /ˈbɑːtəm rɪm/
The bottomrim is the lower edge or border of something round.
She painted the bottomrim of the flowerpot bright blue.
OTHER MEANINGS
2. The lowest circular edge of a wheel or tire.
Mud was stuck all along the bottomrim of the tire.
3. The lower rim of a cup, bowl, or container.
He wiped the bottomrim of the mug before setting it down.
4. The bottom edge of a drum where the skin is attached.
The drummer tightened the bottomrim to change the sound.