The Officiant is the person who conducts or leads a worship service, other than the Holy Eucharist, as in the Morning or Evening Prayer.
The leader of a non-eucharistic worship service.
This is the cleric or secular official that carries out the ceremony. For non religious weddings, he or she might be a justice of the peace, magistrate or even the Captain of a ship (when onboard).
An officiant is someone who officiates at (i.e. leads) a service of Christian worship or some other religious ceremony, such as marriage, burial, or namegiving/baptism. While an officiant or celebrant at a sacrament must be ordained, the same is not true of an officiant at other services.