A meadow (/ˈmɛdoʊ/ MED-oh) is an open habitat or field, vegetated by grasses, herbs, and other non-woody plants. Trees or shrubs may sparsely populate meadows, as long as they maintain an open character. Meadows can occur naturally under favourable conditions but are often artificially created from cleared shrub or woodland for the production of hay, fodder or livestock. Meadow habitats as a group are characterized as semi-natural grasslands, meaning that they are largely composed of species native to the region, with only limited human intervention.

Meadows attract a multitude of wildlife and support flora and fauna that could not thrive in other habitats. They are ecologically important since they provide areas for animal courtship displays, nesting, food gathering, pollinating insects, and sometimes sheltering if the vegetation is high enough. Intensified agricultural practices (too frequent mowing, use of mineral fertilizers, manure and insecticides) may lead to declines in the abundance of organisms and species diversity. There are many types of meadow, including agricultural, transitional, and perpetual – each being a unique and important part of the ecosystem.

Like other biomes, meadows will experience increased pressure (including on their biodiversity) owing to climate change, especially as precipitation and weather conditions change. However grasslands and meadows also have an important climate change mitigation potential as carbon sinks: deep-rooted grasses store a substantial amount of carbon in soil.

In agriculture, a meadow is grassland that is not regularly grazed by domestic livestock but rather allowed to grow unchecked in order to produce hay. Their origins extend back to the Iron Age, when appropriate tools for the hay harvest emerged. The ability to produce livestock fodder on meadows had a significant advantage for livestock production, since animals could be kept in enclosures, simplifying the control over breeding. Surpluses in biomass production during the summer could be stored for the winter, preventing damage to forests and grasslands since there was no longer the need for livestock grazing during the winter.

Especially in the United Kingdom and Ireland, the term meadow is commonly used in its original sense to mean a hay meadow, signifying grassland mown annually in the summer for making hay. Agricultural meadows are typically lowland or upland fields upon which hay or pasture grasses grow from self-sown or hand-sown seed. Traditional hay meadows were once common in rural Britain but are now in decline. Ecologist Professor John Rodwell states that over the past century England and Wales have lost about 97% of their hay meadows. Fewer than 15,000 hectares (37,000 acres) of lowland meadows remain in the UK and most sites are relatively small and fragmented. 25% of the UK's meadows are found in Worcestershire, with Foster's Green Meadow managed by the Worcestershire Wildlife Trust being a major site.

A similar concept to the hay meadow is the pasture, which differs from the meadow in that it is grazed through the summer rather than being allowed to grow out and periodically be cut for hay. A pasture can also refer to any land used for grazing, and in this wider sense the term refers not only to grass pasture but also to non-grassland habitats such as heathland, moorland and wood pasture. The term grassland is used to describe both hay meadows and grass pastures.

The specific agricultural practices in relation to the meadow can take on various expressions. As mentioned, this could be hay production or providing food for grazing cattle and livestock but also to give room for orchards or honey production. Meadows are embedded and dependent on a complex web of socio-cultural conditions for their maintenance. Historically, they emerged to increase agricultural efficiency when the necessary tools became available. Today, agricultural practices have shifted and meadows have largely lost their original purpose. Yet, they are appreciated today for their aesthetics and ecological functions. Consequently, the European Union's Common Agricultural Policy subsidizes their management, mostly through grazing.

A transitional meadow occurs when a field, pasture, farmland, or other cleared land is no longer cut or grazed and starts to display luxuriant growth, extending to the flowering and self-seeding of its grass and wildflower species. The condition is however only temporary, because the grasses eventually become shaded out when scrub and woody plants become well-established, being the forerunners of the return to a fully wooded state. A transitional state can be artificially-maintained through a double-field system, in which cultivated soil and meadows are alternated for a period of 10 to 12 years each.