Word: 凸 (tū) 凸 dictionary entry tū to stick out Full dictionary entry for 凸 Example sentences using 凸 2 sentences, showing page 1 of 1. 人生不是凸的。 Rénshēng bú shì tū de. Life is not convex. 这面镜子中间是凸的。 Zhè miàn jìngzi zhōngjiān shì tū de. This mirror is convex in the middle.