parasites Get Printable Handwriting Hear It! Say It! Write It! Learn It! Spelling Test Definition noun. 1 a plant animal or fungus that lives on or in another living thing called the host; 2 one who lives on the hospitality of others. Example Sentence A healthy diet protects your dog from parasites. Synonyms barnacle; bloodsucker; leech; sponge; hanger-on Antonyms blessing Hear It! Say It! Write It! parasites Switch to cursive Start Share with your friends: