| Part of speech | common noun |
|---|---|
| Hyphenation | tri·an·gul·o |
| Singular | Plural | |
|---|---|---|
| Nominative | triangulo | trianguloj |
| Accusative | triangulon | triangulojn |
| Afrikaans | triangel |
|---|---|
| Catalan | triangle |
| Czech | triangl |
| Danish | triangel |
| Dutch | triangel |
| English | triangle |
| Finnish | triangeli; pimpparauta |
| French | triangle |
| German | Triangel |
| Greek | τρίγωνο |
| Hungarian | triangulum; fémháromszög |
| Italian | triangolo |
| Norwegian | triangel |
| Polish | trójkąt |
| Portuguese | triângulo; ferrinhos |
| Russian | треугольник |
| Spanish | triángulo |
| Swedish | triangel |
| Thai | สามเหลี่ยม |
| Turkish | üçgen |