WordNet (r) 3.0 (2006):

carbonation
    n 1: saturation with carbon dioxide (as soda water)

Moby Thesaurus II by Grady Ward, 1.0:

38 Moby Thesaurus words for "carbonation":
   acetification, acidification, acidulation, alkalization, boiling,
   bubbliness, bubbling, catalysis, chemicalization, ebullience,
   ebulliency, ebullition, effervescence, effervescency, electrolysis,
   ferment, fermentation, fizz, fizzle, foaming, frothiness, frothing,
   hydrogenation, isomerism, metamerism, metamerization, nitration,
   oxidation, oxidization, phosphatization, polymerism,
   polymerization, position isomerism, reduction, saturization,
   sparkle, spumescence, working