leaf Get Printable Handwriting (Leaf) 1 syllables Learn It! Spelling Test Definition noun. andverb. 1 one of the usually green flat parts of a plant or tree that grows from the stem or branch; 2 a sheet of paper usually bound in a book. Example Sentence The leaf fell from the tree. Synonyms green foliage of plant; blade; bract Antonyms plant seed Share with your friends: