The Collaborative International Dictionary of English v.0.48:

Oxyacid \Ox`y*ac"id\, n. [Oxy
   (a) + acid.] (Chem.) An acid containing oxygen, as chloric
       acid or sulphuric acid; -- contrasted with the
       hydracids, which contain no oxygen, as hydrochloric
       acid. See Acid, and Hydroxy-.
       [1913 Webster]

WordNet (r) 3.0 (2006):

oxyacid
    n 1: any acid that contains oxygen [syn: oxyacid, oxygen
         acid]