Without dents; unmarked by dints or impressions.
From Old English 'dynt' + suffix '-less' (without), formed following the productive English pattern of creating adjectives meaning the absence of something.
This is a beautifully logical word that shows how English's '-less' suffix can attach to almost any noun, yet most such combinations are vanishingly rare—'dintless' is historically attested but almost never used today because we just say 'dent-free' instead.
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