It kinda depends how you define “a day”. The usual standard colloquial definition we use would be a “solar day”, i.e. how long it takes for it to go dark and light once each, i.e. noon to noon.

The definition you’re using in this post though is a “sidereal day”, which if you just say “a day” no one would mean, thus this post is misleading. A sidereal day is how long a planet needs to spin around itself.

A Venus “solar (normal) day” (like we normally use the phrase “day”) is 116.75 earth days, while a Venus year is 224.7 earth days. The “sidereal day” that you’re talking about here is 243 earth days long. So a day on Venus is actually shorter than a year on Venus, at least if you use our usual definition of “day”.

Since Venus itself spins opposite to its orbit around the sun, its own spin together with its orbiting around the sun add up together to make the “solar (normal) day” shorter.

An Earth sidereal day is 23 hours 56 minutes while its solar day is 24 hours long. Here, the sidereal day is shorter than the solar day, because the Earth spins in the same direction as its orbit.

Sources: [1] [2]