The Collaborative International Dictionary of English v.0.48:

Oceanography \O`cean*og"ra*phy\, n. [Ocean + -graphy.]
   A description of the ocean.
   [1913 Webster]

WordNet (r) 3.0 (2006):

oceanography
    n 1: the branch of science dealing with physical and biological
         aspects of the oceans [syn: oceanography, oceanology]

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "oceanography":
   altimetry, aquiculture, bathometry, bathymetry, biometrics,
   biometry, cadastration, cartography, chorography, craniometry,
   depth sounding, echo sounding, echolocation, fathomage, fathoming,
   geodesy, geodetics, goniometry, hydrography, hypsography,
   hypsometry, marine biology, mensuration, metrology, planimetry,
   psychometrics, psychometry, sonar, sounding, soundings,
   stereometry, surveying, thalassography, topography, water