wash out

in atmospheric chemistry
https://doi.org/10.1351/goldbook.W06655
The removal from the @[email protected] of gases and sometimes particles by their solution in or @[email protected] to raindrops as they fall.
See also:
rain out (in atmospheric chemistry)
Source:
PAC, 1990, 62, 2167. (Glossary of atmospheric chemistry terms (Recommendations 1990)) on page 2219 [Terms] [Paper]