you'd better believe it

Also, you better believe it. You may be assured, as in You walk ten miles every day?-You'd better believe it! This imperative is almost synonymous with you bet your ass. [Colloquial; mid-1800s]

Common Names:

Name	Pronounced	Usage
Bains	[beinz]
Kumiko	koo-mee-ko	Japanese
Itzal	-	Basque
Androcles	AN-drə-kleez (English)	Ancient Greek (Latinized)
Phunihel	-	Biblical Latin
Barrie	['bæri]