ventilate, air out, vent, air - expose to cool or cold air so as to cool or freshen; "air the old winter clothes"; "air out the smoke-filled rooms"

regenerate, renew - re-establish on a new, usually improved, basis or make new or like new; "We renewed our friendship after a hiatus of twenty years"; "They renewed their membership"

wash up, lave - wash one's face and hands; "She freshened up in the bathroom"

change - undergo a change; become different in essence; losing one's or its original nature; "She changed completely as she grew older"; "The weather changed last night"

alter, change, modify - cause to change; make different; cause a transformation; "The advent of the automobile may have altered the growth pattern of the city"; "The discussion has changed my thinking about the issue"

refreshen, freshen, freshen up, refresh - become or make oneself fresh again; "She freshened up after the tennis game"