christening

Concise Oxford English Dictionary © 2008 Oxford University Press:
christen/ˈkrɪsn/

▶verb

• 1 name (a baby) at baptism as a sign of admission to a Christian Church.

• 2 informal use (something) for the first time.

– derivatives
christener noun,
christening noun.

– origin OE crīstnian ‘make Christian’, from crīsten ‘Christian’, from L. Christianus, from Christus ‘Christ’.