hypsometry (n.)

word-forming element meaning "height," from Greek hypsos "height, top," from PIE *upso-, from root *upo "under," also "up from under," hence also "over" The Greek word is cognate with Sanskrit os "above, over," Old Church Slavonic vysoku "high."

word-forming element meaning "process of measuring," Middle English -metrie, from French -metrie, from Latin -metria, from Greek -metria "a measuring of," from -metros "measurer of," from metron "measure," from PIE root *me- (2) "to measure."