The Collaborative International Dictionary of English v.0.48:
Bathymetric \Bath`y*met"ric\, Bathymetrical \Bath`y*met"ric*al\, a. Pertaining to bathymetry; relating to the measurement of depths, especially of depths in the sea. -- Bath`y*met"ric*al*ly, adv. [1913 Webster]WordNet (r) 3.0 (2006):
bathymetrical adj 1: of or relating to measurements of the depths of oceans or lakes [syn: bathymetric, bathymetrical]