to disguise the source of (illegal or secret funds or profits), usually by transmittal through a foreign bank or a complex network of intermediaries.
b.
to disguise the true nature of (a transaction, operation, or the like) by routing money or goods through one or more intermediaries.
4.
to remove embarrassing or unpleasant characteristics or elements from in order to make more acceptable: He'll have to launder his image if he wants to run for office.
(in ore dressing) a passage carrying products of intermediate grade and residue in water suspension.
8.
Metallurgy. a channel for conveying molten steel to a ladle.
Origin: 1300–50; 1970–75 for def. 3;Middle English: launderer, syncopated variant of lavandere, lavendere washer of linen < Middle French lavandier(e) < Medieval Latin lavandārius (masculine), lavandāria (feminine), equivalent to Latin lavand- (gerund stem of lavāre to wash) + -ārius, -āria-ary; see -er2)