The word "more undecorated" implies something that is lacking in ornamentation or embellishment. Therefore, antonyms for this term would include words that express the opposite meaning, such as decorated, adorned, ornate, embellished, intricate, and fancy. These words all suggest a degree of elaboration or detail that is absent from something that is "more undecorated." By choosing to use antonyms of "more undecorated," one can convey a sense of elegance, refinement, and beauty that is absent from the original term. So, whether you are describing an object, a person, or a place, it is important to consider the opposite meaning of "more undecorated" to help you choose the most precise words.