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凸 (でこ) Japanese meaning | Kotomora

でこ

で

こ

Freq.FrequencyTop 20,000

Meanings

1

noun

usually written using kana alone

Casual word for the forehead, often used in everyday speech. The kanji 凸 visually suggests a protruding shape.

See also: お凸

転ころんででこにたんこぶができた。
I fell and got a bump on my forehead.
彼かれはでこが広ひろいね。
He has a broad forehead, doesn't he?

2

noun

bump; protrusion

usually written using kana alone

Refers to a raised bump or protrusion, often on a surface or the body. The kanji 凸 itself represents a convex shape.

この板いたのでこを削けずって平たいらにしよう。
Let's shave down this bump on the board to make it flat.

Written forms

凸でこ
Kanji form; the shape suggests a protruding bump. Often written in kana in practice.
でこUsage77%
Kana spelling is common.
デコUsage23%

Kanji

凸convex, beetle brow, uneven

Similar words

おでこ
Polite form with honorific prefix お, commonly used for 'forehead' in polite or child-directed speech.
額ひたい
Standard, neutral word for 'forehead'. でこ is more casual and often used in colloquial contexts.

Etymology

The reading でこ is likely derived from 出っこ (でっこ), a colloquial form of 出っ張り (でっぱり, protrusion). The kanji 凸 is a pictograph representing a convex shape, matching the meaning 'bump' or 'protrusion'.