dress (v.)
early 14c., "make straight; direct, guide, control, prepare for cooking," from Old French dresser, drecier "raise (oneself), address, prepare, lift, raise, hoist, set up, arrange, set (a table), serve (food), straighten, put right, direct," from Vulgar Latin *directiare, from Latin directus "direct, straight" (see direct (v.)).

Sense of "decorate, adorn" is late 14c., as is that of "put on clothing." Original sense survives in military meaning "align columns of troops." Dress up "attire elaborately" is from 1670s; dressing down "wearing clothes less formal than expected" is from 1960. To dress (someone) down (1769) is ironical. Related: Dressed; dressing.
dress (n.)
c.1600, originally any clothing, especially that appropriate to rank or to some ceremony; sense of "woman's garment" is first recorded 1630s, with overtones of "made not merely to clothe but to adorn." Dress rehearsal first recorded 1828.