Lily flower; pure
Lillyian is a rare spelling variant of Lillian, which itself is a diminutive of Lily or a derivative of Elizabeth. It combines the floral imagery of the lily flower with the classic suffix -ian, often associated with purity and innocence in Western culture.
Less common today
Lillyian isn't in the latest US Top 1000. It last peaked at #9,637 in 2011.
US births per 5-year period, 1990βpresent (SSA data).