The spring equinox is considered the start of spring in the Northern Hemisphere. Also known as the March equinox or vernal equinox, what it means exactly is that the sun crosses over the line of the equator. With the sun traveling north, it marks the beginning of spring. According to Merriam-Webster, the word "equinox" comes from the Latin words aequi, meaning "equal" and nox, meaning "night." Together, "equinox" means "equal night," which is precisely what the spring equinox is. In all areas throughout the world, both the length of daytime and nighttime are exactly equal.