1.
outie belly button, protruding navel
A belly button that sticks out rather than going inward. A common childhood vocabulary word, as children often notice and comment on belly buttons.
でべそだ！
It's an outie!
Kanji: Can be written as 出べそ or 出臍.
Word formation: 出 (protruding, sticking out) + へそ (臍, belly button). The へ becomes べ due to rendaku.
Childhood context: Children often tease each other about outies, making this a common playground word; the old taunt お前の母ちゃんでべそ ("your mom has an outie") is a stock childish insult.
Medical term: 臍ヘルニア (umbilical hernia) is the medical term for a protruding navel in infants.
Related Words
Related:
臍 (belly button)