Blanching

Sometimes meats like veal, rabbit, or frog were cooked very briefly this way too, both to keep the pale color of the meat and to remove any flavors considered strong.

The word in American cooking eventually became synonymous with the technique more correctly called “parboiling,” which means putting vegetables in a lot of boiling salted water to start their cooking and set their color, then plunging them in ice water to cool. This procedure is also used for vegetables cooked in advance or prior to freezing, in order to preserve their color. It is a fairly nasty technique if you want a fresh vegetable taste.