The term "supremeness" refers to the state or quality of being supreme, which means the highest in rank, authority or power. Its antonyms, on the other hand, refer to the opposite of this concept. Some common antonyms for "supremeness" include inferiority, which means lower in rank or status, subordination, which means being under the control or authority of someone else, and insignificance, which means having little or no importance or value. Other antonyms for "supremeness" may include mediocrity, weakness, or inadequacy. In essence, any word that denotes the opposite of power, status, or significance can be considered an antonym of "supremeness".