For troops in the back of a shuttle there could be thirty seconds of near grayout.

This is called grayout.

Typically an attack occurs while standing and is frequently preceded by a sensation of warmth, nausea, lightheadedness and visual "grayout."

Leaning crookedly against the galley entrance, like a drunk leaning against a lamppost, he saw the things around him go through a shifting, wraithlike grayout.

Mr. Lomax's prophecy of cultural gray-out has been proved wrong, Professor Levin said.

Vigorous hybrids proliferate; the "cultural gray-out" foretold in the 1960's by the folklorist Alan Lomax is not yet in evidence.