Adj. 1. downwind - towards the side away from the wind
lee
leeward - on the side away from the wind; "on the leeward side of the island"
Adv. 1. downwind - with the wind; in the direction the wind is blowing; "they flew downwind"
against the wind, into the wind, upwind - in the direction opposite to the direction the wind is blowing; "they flew upwind"
2. downwind - away from the wind; "they were sailing windward"
windward
leeward, upwind - toward the wind; "they were sailing leeward"

Based on WordNet 3.0, Farlex clipart collection. © 2003-2008 Princeton University, Farlex Inc.

downwind landing = landing in the direction in which the wind is blowing = Rückenwind-...landung

Ändern.

One more vote. I've never seen it as a noun.

Or rather, if I ever saw 'a downwind,' I would guess that it meant 'a (strong) downdraft,' that is, a wind blowing straight down from above.

Would it also help to include 'downwind of so./sth.' and 'upwind of so./sth.'? Those tend to be used in hunting a lot, or in stories about air pollution. If you're downwind of a smell, it comes toward you; if you're upwind of it, you don't smell it as strongly.

I agree that downwind is very odd as a noun. I am only familiar with it as an adj.

M-W:
down·wind
Function: adverb or adjective
: in the direction that the wind is blowing

OALD:
down•wind adv. ~ (of sth) in the direction in which the wind is blowing: sailing downwind * Warnings were issued to people living downwind of the fire to stay indoors. opp upwind
* down•wind adj.

CALD:
downwind
adverb, adjective
in the direction in which the wind blows; with the wind behind:
The smoke drifted downwind.
They live downwind of a pig-farm and sometimes the smell is awful.
Compare upwind.

Chambers:
downwind adverb 1 in or towards the direction in which the wind is blowing; with the wind blowing from behind. 2 behind in terms of wind direction; with the wind carrying one's scent away from (eg an animal one is stalking). adj moving with, or sheltered from, the wind.

Siehe Wörterbuch: downwind

LEO has:
* in Windrichtung
* in Windrichtung liegend
* mit dem Wind
* vor dem Wind
and the nounds Abwind and Fallwind.