noun, noun which may take the genitive case particle 'no'
convex shape; convexity
Describes a shape that bulges outward, like a dome or a lens. Often used in technical or descriptive contexts.
This lens has a convex shape.
Using a convex mirror lets you see a wide area.
Compound of 凸 (とつ, 'convex') and 型 (かた > がた, 'shape, type'). The reading とつ is the on'yomi of the kanji.