As a Noun: 1. A Christian ceremony in which a baby is made a member of the Christian church by being anointed with water and is officially given his or her name. English = christening, (Catholic) baptism. As a Verb or Adjective: 1. Of a baby, to make it a member of the Christian church by anointing it with water and officially giving it a name. English = christen, (Catholic) baptise.