"a region," late 14c., from Old French plage (13c.), from Late Latin plagia "a plain, shore," noun use of adjective (plagia regio), from plaga "a region, stretch of country" (see pelagic). Astronomical sense is from 1949.
"a region," late 14c., from Old French plage (13c.), from Late Latin plagia "a plain, shore," noun use of adjective (plagia regio), from plaga "a region, stretch of country" (see pelagic). Astronomical sense is from 1949.