Comparative form of weakly: more weakly(adjective)
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Use "weaklier" in a sentence
"There would have been no need to expose or put out of the way the weaklier children, for they would have died of themselves."
"Two or three of the weaklier hoggets were dead, from want of air, and from pressure; but more than three-score were as lively as ever; though cramped and stiff for a little while."
"The rest he bullied, and none more than the Bengali, whose weaklier constitution spared him the hard manual work of the yard, but whose timidity invited aggression."