Sister

Derived from the English noun sister meaning "sister". Like in most countries with a culture and language that is ultimately Germanic in origin, this name first started out as an affectionate nickname for a female sibling (who was often older in age, such as the first-born daughter and therefore eldest sister) and over time (due to frequent usage) transformed into an actual given name.

Also compare the names Suster, Syster and Zuster, which are all cognates of this name.