plural mosquitoes also mosquitos
: any of a family (Culicidae) of dipteran flies with females that have a set of slender organs in the proboscis adapted to puncture the skin of animals and to suck their blood and that are in some cases vectors of serious diseases

Illustration of mosquito

Illustration of mosquito

Examples of mosquito in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Limit outdoor activity from dusk to dawn when mosquitoes are most active. Karma Sabbah, CBS News, 10 Sep. 2026 Treat standing water − such as retention ponds or drainage ditches − with a mosquito larvicide. Susan Bromley, Freep.com, 10 Sep. 2026 One case involved research linked to chikungunya, a mosquito-borne virus. Aamir Khollam, Interesting Engineering, 10 Sep. 2026 How to prevent mosquitos in, around your home Much of the mosquito prevention tips from the city's health department involve eliminating standing water from your property. Kaitlyn McCormick, USA Today, 9 Sep. 2026 See All Example Sentences for mosquito

Word History

Etymology

Spanish, diminutive of mosca fly, from Latin musca — more at midge

First Known Use

1572, in the meaning defined above

Time Traveler
The first known use of mosquito was in 1572

Browse Nearby Words

Cite this Entry

“Mosquito.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mosquito. Accessed 13 Sep. 2026.

Kids Definition

mosquito

noun
plural mosquitoes also mosquitos
: any of numerous two-winged flies of which the females have a needlelike structure of the mouth region adapted to puncture the skin and suck the blood of animals
Etymology

from Spanish mosquito "mosquito," literally "little fly," from mosca "fly"

Medical Definition

plural mosquitoes also mosquitos
: any of numerous dipteran flies of the family Culicidae that have a rather narrow abdomen, usually a long slender rigid proboscis, and narrow wings with a fringe of scales on the margin and usually on each side of the wing veins, that have in the male broad feathery antennae and mouthparts not fitted for piercing and in the female slender antennae and a set of needlelike organs in the proboscis with which they puncture the skin of animals to suck the blood, that lay their eggs on the surface of stagnant water, that include many species which pass through several generations in the course of a year and hibernate as adults or winter in the egg state, and that include some species which are the only vectors of certain diseases see aedes, anopheles, culex

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