The Collaborative International Dictionary of English v.0.48:

algarot \al"ga*rot\ ([a^]l"g[.a]*r[o^]t), algaroth \al"ga*roth\
   ([a^]l"g[.a]*r[o^]th), n. [F. algaroth, fr. the name of the
   inventor, Algarotti.] (Med.)
   A term used for the Powder of Algaroth, a white powder
   which is a compound of trichloride and trioxide of antimony.
   It was formerly used in medicine as an emetic, purgative, and
   diaphoretic.
   [1913 Webster]