Definition of the word complementary angle

The term "complementary angle" originated from the Greek word "completo," meaning "fulfill" or "complete." The concept of complementary angles, which refer to angles that add up to 180 degrees in a plane, was first documented by ancient Greeks such as Pythagoras and Euclid. Pythagoras, one of the most prominent philosophers and mathematicians in ancient Greece, is believed to have introduced the concept of complementary angles around the 6th century BCE. Euclid, on the other hand, mentioned complementary angles in his geometry textbook "Elements," which became an authoritative source for mathematics during the medieval period. In the English-speaking world, the word "complementary" first appeared in the Oxford English Dictionary (OED) in the 1400s, meaning "completing" or "making perfect." The mathematical term "complementary angle" was coined in the 19th century to describe angles that sum up to 180 degrees. In summary, the word "complementary angle" has its roots in ancient Greek philosophy and mathematics, where the concept of fulfillment and completeness was established. Its English meaning has since evolved, and its mathematical definition has become a fundamental concept in trigonometry and geometry.