What is making thin, as fluids; diluting; rendering less dense and viscid; diluent. -- n. (Med.) A medicine that thins or dilutes the fluids; a diluent called?

attenuant — Making thin, as fluids; diluting; rendering less dense and viscid; diluent. -- n. (Med.) A medicine that thins or dilutes the fluids; a diluent. (Webster's 1913.)

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