A baby naming ceremony is a humanist

Humanism

Humanism is an approach in study, philosophy, world view or practice that focuses on human values and concerns. In philosophy and social science, humanism is a perspective which affirms some notion of human nature, and is contrasted with anti-humanism....

 or non-religious alternative to ceremonies such as christenings

Infant baptism

Infant baptism is the practice of baptising infants or young children. In theological discussions, the practice is sometimes referred to as paedobaptism or pedobaptism from the Greek pais meaning "child." The practice is sometimes contrasted with what is called "believer's baptism", or...

. The principle is conceptually similar to a civil wedding ceremony as an alternative to a religious wedding ceremony.

The purpose is to recognise and celebrate the arrival of a child and welcome him or her in the family and circle of friends. The structure often mimics that of more traditional naming ceremonies, with a formal ceremony led by a humanist celebrant

Humanist officiant

A Humanist officiant is a person who performs secular humanist celebrancy services for weddings, funerals, child namings, coming of age ceremonies, and other rituals...

 in which the parents name 'guide parents', 'I-don't-believe-in-God-parents' or 'supporting adults' instead of godparent

Godparent

A godparent, in many denominations of Christianity, is someone who sponsors a child's baptism. A male godparent is a godfather, and a female godparent is a godmother...

s. This is often followed by a celebratory party

Party

A party is a gathering of people who have been invited by a host for the purposes of socializing, conversation, or recreation. A party will typically feature food and beverages, and often music and dancing as well....

. However, the event can take whichever form the parents (and the child, if old enough) wish.