- Mathematics The angle formed by two intersecting planes.【数学】 二面角：由两个交叉平面形成的角度
- Aeronautics The dihedral of an aircraft wing.【航空学】 反角：飞机机翼的反角
- co-orbital
- coordinate
- coordinate bond
- coordinate covalence
- coordinated
- coordinated universal time
- Coordinated Universal Time
- coordinates
- coordinate system
- coordinating
- coordinating conjunction
- coordination
- coordination compound
- coordinations
- coos
- Coosa
- coot
- cooter
- cootered
- cootering
- cooters
- cootie
- cootier
- cooties
- cootiest