God
Ellisen is a modern variant of the name Ellison, which originated as an English patronymic surname meaning 'son of Ellis'. Ellis itself is a medieval English form of the Hebrew name Elijah, referring to the biblical prophet. While traditionally masculine, the 'Elli' prefix and 'en' suffix have led to its contemporary use for girls.
Less common today
Ellisen isn't in the latest US Top 1000. It last peaked at #9,434 in 2015.
US births per 5-year period, 1990βpresent (SSA data).