Synonyms of indecipherable

2 Syllables
cramped, cryptic, scrawled
3 Syllables
unsolved, two-by-four
4 Syllables
enigmatic, illegible, insoluble, unconcluded, unreadable, cacographic, hieroglyphic
5 Syllables
irresolvable, inexplicable, undefinable, unexplainable, inexplainable
6 Syllables
unintelligible, undecipherable