right-angled

the term "right-angled" is a modern english compound adjective formed from two distinct roots. the word "right" descends from proto-germanic rehtaz, related to the latin rectus, both carrying the core idea of "straight" or "direct". in geometry, this evolved to specify a line or plane perpendicular to another. "angle" originates from latin angulus (corner), which itself may derive from a proto-indo-european root meaning "to bend". the combination "right angle" emerged to describe the precise, unvarying 90-degree corner, fundamental to architecture and mathematics. the suffix "-ed" is then appended to create an adjective, literally meaning "having the quality of a correct/straight corner", perfectly capturing its geometric definition.

Structure: right (correct, straight) + angle (corner) + ed (adjective suffix) right: from old english riht, meaning "straight, direct, correct". in this compound, it carries the sense of "straight" or "perpendicular". angle: from latin angulus, meaning "corner". it refers to the geometric figure formed by two lines meeting. ed: a middle english suffix from old english -ed, -od, used to form adjectives from nouns, meaning "having the quality of".