Lacking symmetry; not having corresponding parts that are equal in size or arrangement on both sides.
From Greek 'a-' (not) plus 'symmetral', from 'sym-' (together) plus 'metron' (measure), with the Latin suffix '-al'.
This word is even rarer than 'asymmetric' because 'asymmetrical' took over completely—it's like English decided we only needed one word for this and retired the others.
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