The Collaborative International Dictionary of English v.0.48:

Oxygenate \Ox"y*gen*ate\, v. t. [imp. & p. p. Oxygenated; p.
   pr. & vb. n. Oxygenating.] [Cf. F. oxyg['e]ner.] (Chem.)
   To unite, or cause to combine, with oxygen; to treat with
   oxygen; to oxidize; as, oxygenated water (hydrogen dioxide).
   [1913 Webster]

WordNet (r) 3.0 (2006):

oxygenate
    v 1: impregnate, combine, or supply with oxygen; "oxygenate
         blood" [syn: oxygenate, oxygenize, oxygenise,
         aerate]