late 14c., "place for washing;" mid-15c., "act of washing," a contraction (compare launder) of Middle English lavendrie (late 13c.), from Old French lavanderie "wash-house," from Vulgar Latin *lavandaria "things to be washed," plural of lavandarium, from Latin lavare "to wash" (from PIE root *leue- "to wash"). English meaning "articles that need to be or have been laundered" is from 1916. As a verb, from 1880. Laundry list in figurative sense is from 1958.
-ess
fem. suffix, from French -esse, from Late Latin -issa, from Greek -issa (cognate with Old English fem. agent suffix -icge); rare in classical Greek but more common later, in diakonissa "deaconess" and other Church terms picked up by Latin.