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Venus takes about 243 Earth days to rotate once, but about 225 Earth days to orbit the Sun.
A calendar on Venus would be deeply unfamiliar. The planet completes one orbit of the Sun before it has finished a single rotation relative to distant stars. This apparently impossible-sounding result is a real consequence of Venus's extraordinarily slow spin, as documented by NASA.
A different kind of day
Astronomers distinguish between a planet's rotation period and its solar day. A full rotation on Venus takes about 243 Earth days, while its year lasts roughly 225 Earth days. Because Venus rotates in the opposite direction from most planets, the interval from one sunrise to the next is different again: about 117 Earth days. The distinction matters whenever a headline simply says that a day on Venus is longer than its year. It refers to the rotation period, not the sunrise-to-sunrise interval.
Why sunrise would be surprising
Venus rotates retrograde, meaning that it spins in the opposite direction from Earth. From the planet's surface, the Sun would appear to rise in the west and set in the east. Conditions would be far from hospitable to any visitor: the planet has a thick atmosphere, extreme surface pressure and extraordinary heat. Its slow rotation is only one of several ways this nearby world differs from Earth.
What the comparison teaches us
A day and a year are not interchangeable measures of time. A year depends on the orbit around a star; a rotation period depends on how quickly a planet turns. Venus is a useful reminder that the rhythms we regard as ordinary on Earth are not universal.
Sources and further reading
Editorial note: This article explains documented research and links to the primary institutions used to verify its central claims.