Wellformed is an adjective that refers to something which is properly structured, orderly, or follows the rules of grammar. Here are some antonyms for the word "wellformed" that imply the opposite meaning of the term - disordered, misshapen, deformed, unshapely, chaotic, jumbled, confused, incoherent, inchoate, disorganized, scattered, unordered, irregular, abnormal, malformed, and ill-shaped. These antonyms are used to describe something that does not conform to the expected shape, symmetry, or organization, thus creating a sense of disorder, dysfunction, or ambiguity. In summary, Antonyms for wellformed suggest things that are chaotic, disorderly or do not meet the expected norms.