Unmasterfully means to do something without skill, expertise, or proficiency. Its antonyms refer to the opposite, which is to perform a task with expertise, mastery, and finesse. Some antonyms of unmasterfully include skillfully, masterfully, proficiently, expertly, excellently, adeptly, finely, and polished. These antonyms denote the ability to execute a task with accuracy, precision, and confidence. For instance, someone performing an intricate surgery requires the antonym of unmasterfully, which is skillfully, to ensure a successful operation. Similarly, a musician playing a complex piece of music requires the antonym of unmasterfully, which is masterfully, to deliver a flawless performance.