How to spell "undeterminable"

"The exact date of the artifact's creation remained undeterminable after research."

• Letters

  14

• Difficulty

  extreme

• Origin

  Latin

• First letter

  U

• accidentally
• accommodating
• accommodation
• acquiescence
• advantageous
• aforementioned
• anachronistically
• antagonistically
• anthropomorphic
• anthropomorphism
• antidisestablishmentarianism
• apologetically

All extreme wordsMore Latin wordsWords starting with U