Synonyms for Unsymmetrical (same or very similar meaning)
WordNet sense 1 (lacking symmetry):
unsymmetric
WordNet sense 2 (characterized by asymmetry in the spatial arrangement or placement of parts or components):
asymmetric, asymmetrical
WordNet sense 3 (having unsymmetrical parts or unequal dimensions or measurements):
anisometric
WordNet sense 4 (poorly balanced or matched in quantity or value or measure):
unequal
From the ODE community, based on WordNet
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