Superlative form of 'able': the most capable, skilled, or competent of all.
From 'able' (capable) + the superlative suffix '-est'. Old English and Middle English heavily used '-est' for superlatives (best, greatest, fastest) before '-most' became common.
Superlatives like 'ablest' show English's Germanic roots—we got '-est' from Old Germanic languages, which is why we say 'tallest' but French says 'le plus grand' (the most big). Different language families solved superlatives completely differently!
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