Early 17th century (in the sense 'showy dress'): via Italian and Spanish from Old French gale 'rejoicing'.

• gallant from Middle English:

  Gallant at one time could describe an attractive or fine-looking woman. Here is the poet John Lyly writing in 1579: ‘This gallant girl, more fair than fortunate, and yet more fortunate than faithful’. It was also once used to mean ‘excellent, splendid, or noble’, as in ‘A more gallant and beautiful armada never before quitted the shores of Spain’ (William H. Prescott, 1838). Gallant came into English in the Middle Ages in the sense ‘finely dressed’, from Old French galant ‘celebrating’, from gale ‘pleasure or rejoicing’, also the source of gala (early 17th century). The modern sense ‘politely attentive to women’ was adopted from French into English in the 17th century. Gallivant (early 19th century), meaning ‘to go from place to place in pursuit of pleasure’, may be a playful alteration of gallant.