Higgledypiggledy is a term that means disorderly or chaotic. Its antonyms, therefore, would be orderly, neat, tidy, organized, systematic, structured, and arranged. These words describe the opposite of the randomness inherent in higgledypiggledy. For example, a neat room would be the exact opposite of a room that is higgledypiggledy. Similarly, a well-organized schedule would be the opposite of a higgledypiggledy one. Overall, the antonyms for higgledypiggledy describe a state of being well-ordered and put-together rather than disorganized and haphazard.