catheters Get Printable Handwriting Hear It! Say It! Write It! Learn It! Spelling Test Definition noun. a thin flexible tube inserted into the body to permit introduction or withdrawal of fluids or to keep the passageway open Example Sentence The nurse cleaned the patients' catheters. Synonyms tube; tubing for removing fluids; tubular medical device Antonyms fluid Hear It! Say It! Write It! catheters Switch to cursive Start Share with your friends: