13 letters · 19 points in Scrabble
noun the quantity of water falling to earth at a specific place within a specified period of time
noun the process of forming a chemical precipitate
noun the falling to earth of any form of water (rain or snow or hail or sleet or mist)
originFrom Middle French précipitation, from Latin praecipitātiō, praecipitātiōnem. By surface analysis, precipitate + -ion.
Etymology from Wiktionary, CC BY-SA 3.0