The superlative form of tight; most firmly or securely fastened, most snug, or most firmly drawn together.
From Old English 'tiht' meaning 'strong' or 'tight,' combined with the superlative suffix -est. Related to Germanic words for pulling or drawing tight.
The word 'tight' had nothing to do with physical tightness originally—in Old English it meant 'strong' or 'solid,' and only gradually came to mean physically compressed, showing how meanings of words slowly shift over centuries.
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