As early as the 1900s, "to cap" meant to brag, exaggerate or lie about something, according to Dictionary.com. Additionally, "no cap" can be used to describe something that has no limit.

Their average individual income tax cut was only about $6,200, instead of $8,700. The cap had an even greater impact on taxpayers in the top 1%, whose average tax cut was $40,100, instead of $71,000.