Grade 7 triangle Get Printable Handwriting (tri-an-gle) 3 syllables Rhymes Learn It! Spelling Test Definition noun. a figure that has three sides and three angles Example Sentence The rock was shaped like a triangle. Synonyms three-sided polygon; isosceles; three-sided shape Antonyms square; circle Rhymes Three Syllable Rhymes (1) triangle Share with your friends: