phthalide Meaning, Definition & Usage

Phthal"ide noun
Etymology
Phthalyl + anhydride.
Definitions
  1. (Chem.) A lactone obtained by reduction of phthalyl chloride, as a white crystalline substance; hence, by extension, any one of the series of which phthalide proper is the type. Written also phthalid. phthalic anhydride? would be classed as an acid anhydride, rather than a lactone. Obtained commercially by a different process.

Webster 1913