1. most disrespectful or impertinent in speech; most insolent or cheeky
Usage: informal; superlative form of lippy

Examples

• She was the lippiest student in the entire class.
• That was the lippiest response I’ve ever heard from a teenager.
• He became even lippier after his friends arrived, showing off with the lippiest comments.
• The teacher had to deal with the lippiest behavior she’d seen all year.
• Among all the siblings, he was definitely the lippiest when talking to adults.