counterstain

American  

[koun-ter-steyn, koun-ter-steyn] / ˈkaʊn tərˌsteɪn, ˌkaʊn tərˈsteɪn /

noun

1. a second stain of a different color applied to a microscopic specimen and used to color and contrast those parts not retaining the first stain.

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verb (used with object)

1. to treat (a microscopic specimen) with a counterstain.

verb (used without object)

1. to become counterstained; take a counterstain.

counterstain British  

/ ˈkaʊntəˌsteɪn /

verb

1. to apply two or more stains in sequence to (a specimen to be examined), each of which colours a different tissue

2. (tr; usually passive) to apply (one of a series of stains) to a specimen to be examined

   haematoxylin is counterstained with eosin

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Etymology

Origin of counterstain

First recorded in 1890–95; counter- + stain