seatbelt Get Printable Handwriting Hear It! Say It! Write It! Learn It! Spelling Test Definition noun. a strap or belt that holds a person in a seat. Example Sentence Trudy buckled her seatbelt as soon as she got in the car. More Example Sentences Always wear a seatbelt while driving. Synonyms safety belt; harness; restraint Hear It! Say It! Write It! seatbelt Switch to cursive Start Share with your friends: