black arm

American  

noun

Plant Pathology.

1. a type or phase of bacterial blight of cotton, characterized by black, elongated lesions on the stem and branches, caused by a bacterium, Xanthomonas malvacearum.

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Etymology

Origin of black arm

First recorded in 1905–10

Example Sentences

In 1969, the Warren Court ruled for high school students who wore black arm bands as a protest.

From Los Angeles Times • May 27, 2025

The Süddeutsche Zeitung, in its coverage of the Cologne attacks, prominently featured an illustration of a woman’s legs silhouetted in white, with the space in between taken up by a black arm and hand.

From The Guardian • Aug. 1, 2019

Turmoil at home has never been far from the minds of the Ukrainian team, and some athletes asked for permission on Wednesday to wear black arm bands while competing in order to honor those killed.

From Reuters • Feb. 20, 2014

We tied black arm bands on our left biceps in memory of cyclists who had died in collisions with motorists.

From Salon • Jun. 6, 2013

Swiftly, the man pushed Minli aside and began to pour the liquid from the medicine jar over Dragon’s black arm.

From "Where the Mountain Meets the Moon" by Grace Lin