HYDROGRAPHY
hydrography
(noun) the science of the measurement and description and mapping of the surface waters of the earth with special reference to navigation
Source: WordNet® 3.1
Etymology
Noun
hydrography (countable and uncountable, plural hydrographies)
(nautical) The scientific measurement and description of the physical features and conditions of navigable waters and the shoreline.
Source: Wiktionary
Hy*drog"ra*phy, n. Etym: [Hydro-, 1 + -graphy: cf. F. hydrographie.]
1. The art of measuring and describing the sea, lakes, rivers, and
other waters, with their phenomena.
2. That branch of surveying which embraces the determination of the
contour of the bottom of a harbor or other sheet of water, the depth
of soundings, the position of channels and shoals, with the
construction of charts exhibiting these particulars.
Source: Webster’s Unabridged Dictionary 1913 Edition