indeterminable
adjective
1. not capable of being definitely decided or ascertained
Similar word(s): incalculable, indeterminate, unascertainable, undiscoverable, unpredictable, indeterminate, undetermined, undeterminable
2. incapable of being definitely ascertained or calculated
Similar word(s): incalculable
noun
1. An indeterminable thing or quantity.