This is the 8632nd most frequent French word.
arroser
To water or to sprinkle.
In this sentence, 'arroser' means to water, specifically referring to the action of providing plants with water for care or nourishment.
J'arrose les plantes tous les matins.
I water the plants every morning.
Here, 'arroser' metaphorically means celebrating an event, typically by drinking or serving a beverage as part of the festivity.
Nous avons arrosé ce grand événement avec du champagne.
We celebrated this big event with champagne.
In this passive construction, 'arroser' describes gardens being naturally watered by rainfall.