Undeterminably is an adverb that refers to the inability to determine or identify certain things or situations. Synonyms for this word include indeterminately, uncertainly, indefinitely, inconclusively, vagueness or hazily. These words describe situations where there is no clear or conclusive answer for something or when an event or circumstance is vague or ambiguous. Additionally, phrases such as "up in the air" or "yet to be determined" are also synonyms for undeterminably. Overall, these synonyms convey a sense of ambiguity and uncertainty that may need to be resolved through further investigation or clarification.