also: おうがた
noun, noun which may take the genitive case particle 'no'
concave shape; concavity
Refers to a shape or form that is indented or hollowed inward. Often used in technical, design, or descriptive contexts. Antonym: 凸形 (convex shape).
Antonyms: 凸形
このレンズは凹形をしている。
This lens has a concave shape.
凹形の鏡を使うと、像が小さく映る。
When you use a concave mirror, the image appears smaller.
凸形 means convex shape, the opposite of 凹形. Both are technical terms for describing surface curvature.
Compound of 凹 (concave) and 形/型 (shape/form). The reading おうけい is the on'yomi of the kanji, while おうがた combines on'yomi and kun'yomi. The exact historical derivation is uncertain, but the word is a straightforward technical term.