Lightweight/ˈlaɪtweɪt/ Definition 1 of 4Pro Tip 1/2Comparative Context Often used to compare one person's abilities or qualities against others. Despite his efforts, he's still a lightweight in the world of chess. Pro Tip 2/2Not for Disrespect Even if it means 'less serious', it's not always used to disrespect someone. He's a bit of a lightweight, but we love his cheerful attitude.