When somebody tells you something, and you dismiss it as being lip gloss, what you mean is that the person is exaggerating. The term can be used to mean to lie or exaggerate.
Examples: “Don’t believe anything that the Registrar said during the meeting. His words are just lip gloss.” * According to Dharmendra, everything Gayathri says is just lip gloss. The woman is a born liar.
The expression `lip gloss’ is mostly used in informal contexts.