Slit/slɪt/ Definition 1 of 2Pro Tip 1/3Physical Dimension Used to describe physical features that are thin and elongated. There was a thin slit in her dress to show off the shoe. Pro Tip 2/3Visibility Hint Often implies that something is barely visible or could be looked through. He peered through the slit in the curtains to see outside. Pro Tip 3/3Not Always Straight Slits can be curved or irregular, not necessarily a straight line. The vase had a looping slit pattern around its neck.