roccellic acid

== English == === Etymology === From French roccellique, from roccelle (“archil”), from Italian roccella, from rocca (“a rock”), because archil grows on rock. === Noun === roccellic acid (uncountable) (chemistry) A dibasic acid, C17H32O4, of the oxalic series, found in archil (Roccella tinctoria, etc.), and other lichens. === References === “roccellic”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.