godan verb (-su), transitive verb
wash away; rinse off
Used for removing dirt, stains, or unwanted substances by washing or rinsing, often with water.
泥を洗い流す。
Wash away the mud.
シャンプーをしっかり洗い流してください。
Please rinse off the shampoo thoroughly.
Compound of 洗い (continuative form of 洗う 'wash') + 流す ('let flow').