In the direction of the breadth; across the width rather than along the length.
From 'breadth' plus the suffix '-ways' (Old English 'wægnes'). This directional adverb follows the pattern of 'lengthways' and 'sideways'.
Sewing instructions and fabric guides use 'breadthways' to tell you whether to cut a pattern along or across the grain—it's a word that survives because efficiency in textiles demands precision.
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