Trapézio vs. trapezoide
In Portuguese geometry, the distinction between trapézio and trapezoide relies entirely on the presence of parallel sides. While trapézio is a shape with one pair of parallel sides, trapezoide refers to a four-sided shape with no parallel sides. Note that these definitions align with British English usage (Trapezium/Trapezoid) but are the opposite of American English usage.
Trapézio
B2This word refers to a quadrilateral with exactly one pair of parallel sides (known as bases). Beyond geometry, trapézio also refers to the large muscle in the upper back and neck, as well as the swing apparatus used by circus acrobats.
Para a prova de matemática, tivemos que calcular a área do trapézio.
(For the math test, we had to calculate the area of the trapezoid.)
O artista de circo balançava no trapézio com muita coragem.
(The circus artist swung on the trapeze with great courage.)
Sinto muita tensão no meu trapézio depois de trabalhar no computador.
(I feel a lot of tension in my trapezius muscle after working at the computer.)
Um trapézio isósceles tem os lados não paralelos de igual comprimento.
(An isosceles trapezoid has non-parallel sides of equal length.)
A saia dela tinha um corte em forma de trapézio.
(Her skirt had a trapezoid-shaped cut.)
Trapezoide
C1This term describes a quadrilateral in which no two sides are parallel to each other. In anatomy, trapezoide is also the name of a specific carpal bone located in the human wrist.
Como a figura não tem lados paralelos, ela é classificada como um trapezoide.
(Since the figure has no parallel sides, it is classified as a trapezium.)
O terreno que compramos é um trapezoide totalmente irregular.
(The plot of land we bought is a completely irregular trapezium.)
O osso trapezoide é o menor osso na fileira distal do carpo.
(The trapezoid bone is the smallest bone in the distal row of the carpus.)
Diferente do quadrado, os ângulos internos de um trapezoide variam muito.
(Unlike a square, the internal angles of a trapezium vary greatly.)
O professor pediu para desenhar um trapezoide assimétrico.
(The teacher asked to draw an asymmetrical trapezium.)
Summary
To distinguish between these terms, look for parallelism. Use trapézio for shapes with one pair of parallel sides, back muscles, or circus swings. Use trapezoide for irregular four-sided shapes with no parallel lines or for the small bone in the wrist.