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

In the United States, spiders that are dangerous to people include the brown recluse, which carries a necrotic toxin that destroys tissue, and the black widow, which has a special neurotoxin that damages nerve cells. —Matthew Cordes, The Conversation, 6 Apr. 2026

This includes brown and black widows and brown recluse. —Arricca Elin Sansone, Southern Living, 2 Apr. 2026

Meanwhile, successful female contestants like two-time champion Parvati Shallow have been framed as snakes and black widows. —Joe Reid, Vulture, 1 Apr. 2026

Warmer temperatures due to climate change might be affecting grubs, said Fyffe, who is seeing more uncommon arthropods like black widow spiders in Chicago than in past years. —Laura Turbay, Chicago Tribune, 13 Mar. 2026

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