black widow

American  

noun

1. a venomous spider, Latrodectus mactans, widely distributed in the U.S., the female of which is jet-black with an hourglass-shaped red mark on the underside of its abdomen.

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black widow British  

noun

1. an American spider, Latrodectus mactans , the female of which is black with red markings, highly venomous, and commonly eats its mate

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Etymology

Origin of black widow

First recorded in 1910–15

Example Sentences

Roger Romani of Stanford University and the Kavli Institute for Particle Astrophysics and Cosmology is one of the world's leading experts on black widow systems.

From Science Daily • Jan. 1, 2026

Verrelli has studied the spread of black widow spiders, an increasing medical health concern in cities along the West Coast.

From Salon • Jun. 15, 2025

Hunting at night for crabs and avoiding being bitten by black widow spiders, he tells the cameras: "I'll be slammed for this Phillip Schofield mad rant."

From BBC • Sep. 28, 2024

It’s much more common to find a false black widow indoors, which are from a different genus and are less toxic than black widows, Vetter said.

From Los Angeles Times • Aug. 7, 2024

He watched it passively for a moment, until of a sudden he realized it was a female black widow doing her thing not three feet from his toes.

From "The Milagro Beanfield War" by John Nichols