foul-weather

The compound adjective 'foul-weather' is a straightforward combination of two ancient English words. 'Foul' originates from a Proto-Germanic root meaning rotten or putrid, a sense that broadened to describe anything morally or physically offensive, including stormy, dirty, or unpleasant conditions. 'Weather' stems from a Germanic root referring broadly to wind, storm, and the state of the atmosphere. The logic of the compound is transparent: it literally describes weather that is 'foul'—stormy, rainy, or inclement. This term, particularly in nautical contexts, evolved to classify gear, clothing, or preparations specifically intended for such adverse conditions, moving from a simple description to a functional classifier.

Structure: foul (dirty, unpleasant) + weather (atmospheric conditions) - foul: From Old English fūl (rotten, unclean, vile), from Proto-Germanic fūlaz. Functions as an adjective modifying 'weather'. - weather: From Old English weder (air, sky, storm, wind), from Proto-Germanic wedrą. Functions as the noun being modified.