The Collaborative International Dictionary of English v.0.48:

Squinance \Squin"ance\ (skw[i^]n"ans), Squinancy \Squin"an*cy\
   (-an*s[y^]), n. [F. esquinancie, OF. squinance, esquinance.
   See Quinsy.]
   1. (Med.) The quinsy. See Quinsy. [Obs.]
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   2. (Bot.) A European perennial herb (Asperula cynanchica)
      with narrowly linear whorled leaves; -- formerly thought
      to cure the quinsy. Also called quincewort.
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   Squinancy berries, black currants; -- so called because
      used to cure the quinsy. --Dr. Prior.
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