A medicine that serves for many uses, or that cures many diseases.(noun)
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Use "polychrest" in a sentence
"The four mathematical instances measure practice: polychrest and magical instances facilitate it."
"There remains a consent of bodies, inartificial perhaps in mode of operation, but in use a polychrest, which should in no wise be omitted, but examined into with careful attention."
"Let this suffice to exemplify the polychrest instances."