CHALLENGINGchallenging · English · Reference checkedReferenceOpen English WordNet 2024oewn2024:lemma:CHALLENGINGTier 1Ordinal92Pythagorean56Classical88Reverse205Reverse Reduction52Standard184Final Large184Ordinal76Reduced31Atbash558Isopsephy782Ordinal98Abjad203