[1] : The Collaborative International Dictionary of English v.0.48

christen \chris"ten\, v. t. imp.  p. p. christened; p. pr. 
   vb. n. christening. as. cristnian to make a christian,
   fr. cristen a christian.
   1913 webster
   1. to baptize and give a christian name to.
      1913 webster

   2. to give a name; to denominate. "christen the thing what
      you will." --bp. burnet.
      1913 webster

   3. to christianize. obs. --jer. taylor.
      1913 webster

   4. to use for the first time. colloq.
      1913 webster
see also:
christened christening 

[2] : WordNet (r) 2.0

christening
     n : giving a christian name at baptism

[3] : Moby Thesaurus II by Grady Ward, 1.0

24 moby thesaurus words for "christening":
   affusion, appellation, aspergation, aspersion, baptism,
   baptismal gown, baptismal regeneration, baptistery, baptizement,
   calling, chrismal, definition, denomination, designation, font,
   identification, immersion, infusion, naming, nicknaming,
   sprinkling, styling, terming, total immersion

Christening >> C Words
Christening, definition of term: Christening
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