A tailwind is a wind blowing from behind you, in the same direction you are going. It pushes you along, so you go faster and use less energy. Pilots, sailors, cyclists and runners talk about it constantly: with a strong tailwind a flight from Taipei to Los Angeles can land half an hour early, and a cyclist can feel suddenly, wonderfully strong. Its opposite is a headwind, which blows into your face and slows you down. Because the picture is so clear, the word is used very often in a figurative way, especially in business and news writing: a tailwind is anything outside your control that helps you along — low interest rates, a weak currency, a new law that happens to suit your industry. "Falling oil prices gave airlines a tailwind last year." In that use it is usually plural — "tailwinds" — and it is paired with "headwinds" for the things making life harder. Note the small oddity in athletics: a race time only counts as a record if the tailwind is under 2.0 metres per second, because too much help from behind is not really the runner's own speed. Also, careful — for pilots a tailwind is not always good news: landing with a tailwind is harder, because the plane needs the wind in its face to slow down.