kind of seaweed, c. 1600, Latin, from Greek zōstēr "girdle," originally "warrior's belt," from zōnnynai (see zone (n.)). Meaning "shingles" is from 1706; in the literal sense, "a belt or girdle, especially for men," from 1824.

"inflammatory disease of the skin," late 14c., from Medieval Latin cingulus, a variant of Latin cingulum "girdle," from cingere "to gird" (see cinch (n.)). The medical use of the word in Medieval Latin is a loan-translation of Greek zōstēr, literally "girdle." The inflammation was so called because it often extends around the middle of the body, like a girdle. Perhaps it was reinforced in English by the plural of French cengle "shingles," literally "belt, fence," from the same Latin word.