black widow

noun

: a venomous New World spider (Latrodectus mactans of the family Theridiidae) the female of which is black with an hourglass-shaped red mark on the underside of the abdomen

broadly : any of various related venomous spiders that have a large globular, usually glossy, dark abdomen often marked with red and long and wiry legs

Illustration of black widow

Examples of black widow in a Sentence

Recent Examples on the Web

The name refers to the black widow spider, whose female is known for killing the male after mating — a metaphor that underscores the cold and calculated betrayal at the heart of the case. —Isadora Wandermurem, Time, 30 May 2025

In 1939, the London Zoo killed more than 200 animals, starting with the black widow spiders and venomous snakes. —John M. Kinder, The Conversation, 1 May 2025

Javadi winds up working on one of her mother’s Crohn’s patients and realizes this woman isn’t suffering from a perforated bowel but rather from a black widow spider bite. —Maggie Fremont, Vulture, 20 Feb. 2025

And disconcerting moments are in the show, such as the larger-than-life black widow spiders that dangle from the ceiling. —Dewayne Bevil, Orlando Sentinel, 19 Feb. 2025

Word History

First Known Use

1830, in the meaning defined above

Rhymes for black widow

• kiddo

Kids Definition

black widow

noun

: a poisonous New World spider the female of which is black with an hourglass-shaped red mark on the underside of the abdomen

Medical Definition

black widow

noun

black wid·​ow -ˈwid-ˌō 

: a venomous New World spider of the genus Latrodectus (L. mactans) the female of which is black with an hourglass-shaped red mark on the underside of the abdomen

broadly : any other spider of the genus Latrodectus