n. [ F. ] 1. (Cookery) A frozen dessert of a frothy texture, made of sweetened and flavored whipped cream, sometimes with the addition of egg yolks and gelatin. Mousse differs from ice cream in being beaten before -- not during -- the freezing process. [ Webster 1913 Suppl. ]
2. Any of a variety of foods whipped to a light texture; as, a salmon mousse. [ PJC ]
3. A foam containing special chemicals, used for styling hair. [ PJC ]
Mousseline de laine [ F., muslin of wool. ] Muslin delaine. See under Muslin. -- Mousseline glass, a kind of thin blown glassware, such as wineglasses, etc. [ 1913 Webster ]