complementary angle 
noun
Either of two angles whose sum is 90°.Angle A and angle B are complementary angles....
- It took a full fifteen minutes for him to understand supplementary and complementary angles.
- So what happened to him was that he was struck and flung in a north-easterly direction generally and he came out again at a complementary angle in a south-easterly direction until he was lying on the fog line.
- bouquet
- bouquet garni
- Bourbaki, Nicolas
- bourbon
- Bourbon County
- Bourbonnais
- Bourbon rose
- bourdon
- Bourdon gauge
- bourg
- bourgade
- bourgeois
- bourgeoisdom
- bourgeoise
- bourgeoisie
- bourgeoisification
- bourgeoisified
- bourgeoisify
- bourgeoisistic
- bourgie
- Bourgogne
- Bourguiba, Habib ibn Ali
- Bourguignonne
- Bourke
- Bourke-White, Margaret