But, as David Koyzis writes, that may not be the case:
There is still no general agreement on the origin of the word, but it has been suggested that it may come, not from the name of a goddess, but from eostarun, the Old High German word for the dawn itself. (Our word east obviously has similar origins.) In fact there are some remarkable similarities between the words for resurrection, Easter and dawn in several Indo-European languages. The common meaning underlying these words is a rising of some sort.
If our own word Easter originally meant sunrise, then perhaps it was fittingly applied to the Rising of the Son of God from the dead by our Teutonic forebears. And if this is so, then it seems that we English-speakers do after all have a most appropriate name for the feast of Christ’s Resurrection.