Wiktionary
n. A drainage wind / fall wind: a wind, such as the bora or Böhmwind, which moves high density air from a higher elevation down an incline, due to the force of gravity.
WordNet
n. a wind caused by the downward motion of cold air [syn: catabatic wind]
Wikipedia
A katabatic wind, from the Greek word κατάβᾰσις katabasis meaning "descending", is the technical name for a drainage wind, a wind that carries high density air from a higher elevation down a slope under the force of gravity. Such winds are sometimes also called fall winds. Katabatic winds can rush down elevated slopes at hurricane speeds, but most are not as intense as that, and many are of the order of 10 knots (18 km/h) or less.
Not all downslope winds are katabatic. For instance, winds such as the föhn, chinook, and bergwind are rain shadow winds where air driven upslope on the windward side of a mountain range drops its moisture and descends leeward drier and warmer. Examples of true katabatic winds include the bora (or bura) in the Adriatic, the Bohemian Wind or Böhmwind in the Ore Mountains, the Santa Ana in southern California, and the oroshi in Japan. Another example is "the Barber", an enhanced katabatic wind that blows over the town of Greymouth in New Zealand when there is a southeast flow over the South Island. It is a wind that is known in the area for its coldness.
Usage examples of "katabatic wind".
A katabatic wind was pouring down Kasei Vallis and onto Chryse Gulf.
When Smallwood had dropped us off we had been fairly into the steadily deepening depression in the ice-cap that wound down to the Kangalak glacier and it was a perfect drainage channel for the katabatic wind that was pouring down off the plateau.
It was a part-katabatic wind, he'd been told by somebody: a current of cold air flowing down from the ice-locked wastes above, displacing warmer, less dense air below and driving gently but firmly downwards, spilling over the lip of the waterfall like a ghost of the frozen, plunging waters.
A katabatic wind was growing, pouring down from the higher slopes above the camp.
Below him, the first slanting rays of the linked suns had penetrated almost to the bottom of the valley, where they lit the spectacle of the phagors fording the katabatic wind, their sturdy bodies enmeshed in writhing fog, the stiff hairs of their coats stirred in their progress.