undulations Get Printable Handwriting Hear It! Say It! Write It! Learn It! Spelling Test Definition noun. 1 to form or move in waves; 2 to have a wavelike appearance or motion. Example Sentence Bill began to feel ill from driving on the steep undulations of the road. Synonyms wave; fluctuation; roll; sway; waviness Antonyms stillness Hear It! Say It! Write It! undulations Switch to cursive Start Share with your friends: