Denshi Jisho — Online Japanese dictionary

凸 でこ brow; forehead
Noun, Usually written using kana alone, Sensitive 
凸 とつ convex
Na-adjective, No-adjective 
凸凹 でこぼこ unevenness; roughness; ruggedness
Common word, Na-adjective, Noun, No-adjective 
凸版 とっぱん letterpress; relief printing
Common word, Noun, No-adjective 
凸坊 でこぼう beetle-browed boy; mischief
Noun 
凸角 とっかく convex angle
Noun 
凸円 とつえん convexity
Noun 
凸凹 とつおう unevenness; roughness; ruggedness
Na-adjective, Noun, No-adjective 
凸形 とつけい convex; cuspid; gibbous
No-adjective, Noun 
凸面 とつめん convex surface; convex
Noun, No-adjective 
凸柑 ポンかん ponkan orange (Citrus reticulata); tangerine
Ateji (phonetic) reading, Noun, Usually written using kana alone 
凸鏡 とっきょう convex mirror
Noun 
凸状 とつじょう protrusion
Noun, No-adjective 
凸凹紙 とつおうし embossed paper
Noun 
凸レンズ とつレンズ convex lens
Noun 
凸集合 とつしゅうごう convex set
Noun, Mathematical term 
凸面鏡 とつめんきょう convex mirror
Noun 
凸多角形 とつたかくけい convex polygon
Noun 
凸版印刷 とっぱんいんさつ letterpress; relief printing
Common word, Noun, No-adjective 

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