A veil is a cloth covering the head and face, mostly worn by women. Wedding veils are drawn back when the groom hears, "Now you may kiss the bride." (Or else the groom gets a gauzy mouthful.)
This is a technical term for part of an embryo or mushroom, but it’s usually a covering for the head and face. Priests wear veils during certain Catholic ceremonies, and a grieving widow might wear a veil at her husband's funeral. To veil also means to conceal something. You could veil your attempt to steal some cookies by turning the TV up loud as a distraction. When something — like a lie — is "thinly veiled," people can see right through it.