This is the 1078th most frequent French word.
blanche
"Blanche" means "white" (feminine form) in English.
Here, 'blanche' is used as an adjective in feminine form to describe the color of 'la neige' (the snow).
La neige est blanche.
The snow is white.
In this case, 'blanche' modifies 'robe', a feminine noun, again as an adjective that describes its color.
Marie porte une robe blanche.
Marie is wearing a white dress.
Here, 'blanche' is used as an adjective in feminine form to describe 'maison' (house), indicating its color.