Superlative form of bland; the most dull, tasteless, insipid, or uninteresting.
From 'bland' plus the superlative suffix '-est.' The superlative indicates the extreme degree of the quality described by the adjective.
English has two ways to make superlatives—short words use '-est' (blander→blandest) while longer words use 'most' (interesting→most interesting), a pattern from Old English still alive in modern speech.
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