yellow jacket
noun
plural yellow jackets
1
or yellowjacket
ˈye-lō-ˌja-kət
plural yellowjackets
: any of various small vespid wasps (genus Vespula and Dolichovespula) typically with abdomens marked with yellow and black that build nests in the ground or less commonly in aerial locations (such as the eaves of buildings), that usually reach a length of up to .5 inches (1.3 centimeters), and that can sting repeatedly and painfully
ˈye-lə-
2
slang
: pentobarbital especially in a yellow capsule
—usually used in plural
Cite this Entry
“Yellow jacket.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/yellow%20jacket. Accessed 10 Aug. 2026.
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