[adv] in a malignant manner, as of a tumor that spreads
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balefully, banefully, corrodingly, corrosively, counterproductively, damagingly, deleteriously, detrimentally, disadvantageously, disserviceably, harmfully, hatefully, hurtfully, in spite, iniquitously, injuriously, invidiously, malefically, maleficently,
\Ma*lig"nant*ly\, adv. In a malignant manner.