barrier island Get Printable Handwriting Hear It! Say It! Write It! Learn It! Spelling Test Definition noun. a narrow strip of sand that forms an offshore landform separated from the main shoreline Example Sentence The barrier island protects the mainland from the force of ocean waves. Synonyms fence; barricad; blockage Antonyms exposed Hear It! Say It! Write It! barrier island Switch to cursive Start Share with your friends: