co-altitude

OSBORN: He would come up close, co-altitude, within about three to five feet, was making gestures.

CNN Transcript Apr 14, 2001 2001

As the distance from the horizon to the zenith is 90°, the difference, or _complement_ of the altitude, is called the _zenith distance_, or _co-altitude_.

Scientific American Supplement, No. 360, November 25, 1882 Various

Slokes immediately threw the jet off its course, and Snitch punched out some chaff and flares (the chaff distracts radar guidance, and the flares confuse a heat-seeker), after which ensued thirty weighty seconds — or, as Snitch puts it, "half the known age of the universe" — of listening to each other's nervous breathing in the headphones, waiting to be torn into oblivion, until the pilot of a trailing jet commented, in perfect pilotese, "It burned out co-altitude."

The Kabul-ki Dance 2002

Slokes immediately threw the jet off its course, and Snitch punched out some chaff and flares (the chaff distracts radar guidance, and the flares confuse a heat-seeker), after which ensued thirty weighty seconds — or, as Snitch puts it, "half the known age of the universe" — of listening to each other's nervous breathing in the headphones, waiting to be torn into oblivion, until the pilot of a trailing jet commented, in perfect pilotese, "It burned out co-altitude."

The Kabul-ki Dance 2002