ETYM Latin praecipitatio: cf. French précipitation.
In meteorology, water that falls to the Earth from the atmosphere. It includes rain, snow, sleet, hail, dew, and frost.
1. An unexpected acceleration or hastening.
2. The falling to earth of rain or snow or hail or sleet or mist; SYN. downfall.
3. The process of forming a chemical precipitate.