Arendje

When borne by a female person, this name is a good example of how one can turn a very masculine name (Arend) into a feminine name by simply adding the diminutive suffix -je to the original name. But when borne by a male person, this name is simply a pet form because of the diminutive suffix. Also compare Arentjen, which is the medieval form of this name. Arenda is also worth a look, since it is also a feminine form of Arend (though a much less common one at that).

Lastly, it might be interesting to know that arendje is also an independent word in the Dutch language and means "little eagle" in English. However, cases where Arendje as a given name was inspired by this word are likely to be few to none, due to the prevalence of Arendje as a proper given name that - via Arend - is ultimately derived from the Germanic given name Arnold.