indecidability means undecidability. Lexicurio rates it Sui generis — a strength score of 97 out of 100.
Why “indecidability” is a great word
INDECIDABILITY — [Noun] The property of a proposition or problem for which no algorithm or effective procedure can determine a definite yes-or-no answer. From the English prefix in- ("not") + decidability, the latter from decide, ultimately from the Latin decidere ("to cut off, decide"). Unlike "ambiguity," a semantic fog of multiple meanings, or "undecidability," its more rigorously formal counterpart, indecidability denotes a proven structural impossibility of resolution. It is the Gödelian sentence that can neither be proven nor disproven, the Turing machine that will never halt, the labyrinth constructed without a center—a quiet demonstration that some doors in the mansion of reason are built without keys.
Etymology
From in- + decidability.
noun
- undecidability“The text's indecidability is elaborated in terms of and as an operative feature of its textuality.”