cast-iron

a cast-iron promise or arrangement is one that can be trusted completely (always before noun) No new business comes with a cast-iron guarantee of success.

Common Names:

Name	Pronounced	Usage
Averill	-	English (Rare)
Remigius	-	Late Roman
Brenton	BREN-tən	English
Elnathan	el-NAY-thən (English)	Biblical
January	['dʒænjuəri]
Yefim	ye-FEEM, ee-FEEM	Russian