*A fourth dimension can be time.

Time is a very convenient choice for a fourth dimension, but “fourth” is purely namesake. There’s no reason we couldn’t describe our world in our three familiar spatial coordinates with an additional coordinate for temperature, for example. We just don’t easily conceptualize it that way because it feels less contiguous according to how we currently frame our model of reality.

Disclaimer: my sources include internet research and far too much time to think. I’m absolutely open to discussion and new ideas in whatever form.