"Workably" is a challenging term to find opposite words because it is an adverb that describes something that can be done or accomplished. However, some phrases that can be used as antonyms for "workably" are "impractically," "unfeasibly," "impracticably," "impracticability," "unattainable," "unworkable," and "impossible." These antonyms describe something that is either too difficult, impractical, or impossible to achieve, which can be considered as opposite to "workably." Overall, it can be tough to find antonyms for this term, but knowing some phrases that can be used as antonyms can help convey the right meaning in sentences.