An umbo is a raised nipple-y area in the center of a mushroo..
Added 2021-09-25 22:24:28 +0000 UTCAn umbo is a raised nipple-y area in the center of a mushroom cap. You know, I umbo, You umbo, He she me umbo, Umbology, The study of umbo? It's first grade SpongeBob! πππππππ
