Definition of complementary angle in English:

complementary angle

noun

  • Either of two angles whose sum is 90°

    • ‘Angle A and angle B are 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.’
    • ‘It took a full fifteen minutes for him to understand supplementary and complementary angles.’