Revitalization is the act of putting new strength into something that has grown weak or tired. People use it for places (an old street, a town centre), for jobs and money (a country’s economy), and sometimes for a language or a club that almost nobody cares about any more. It sounds a little official — a government plan, a newspaper headline — not a text to a friend. Though actually the feeling underneath is simple: something was fading, and energy is being pushed back in on purpose. It sits near revival, but revival often means a religion or a fashion coming back by itself; revitalization more often means a place or a system being given new power as a project. In British spelling you may see revitalisation; the meaning is the same.