The papaya (/pəˈpaɪə/ or US /pəˈpɑːjə/) (from Carib via Spanish), papaw, (/pəˈpɔː/) or pawpaw (/ˈpɔːˌpɔː/)  is the plant Carica papaya, one of the 22 accepted species in the genus Carica of the family Caricaceae.

It is native to the tropics of the Americas, perhaps from southern Mexico and neighboring Central America. It was first cultivated in Mexico[citation needed] several centuries before the emergence of the Mesoamerican classical civilizations.

The papaya is a small, sparsely branched tree, usually with a single stem growing from 5 to 10 m (16 to 33 ft) tall, with spirally arranged leaves confined to the top of the trunk. The lower trunk is conspicuously scarred where leaves and fruit were borne. The leaves are large, 50–70 cm (20–28 in) in diameter, deeply palmately lobed, with seven lobes. All parts of the plant contain latex in articulated laticifers. Unusually for such large plants, the trees are dioecious. The flowers are 5-parted and highly dimorphic, the male flowers with the stamens fused to the petals. The female flowers have a superior ovary and five contorted petals loosely connected at the base.:235 Male and female flowers are borne in the leaf axils, the males in multiflowered dichasia, the female flowers is few-flowered dichasia. The flowers are sweet-scented, open at night and are moth-pollinated. The fruit is a large berry about 15–45 cm (5.9–17.7 in) long and 10–30 cm (3.9–11.8 in) in diameter.:88 It is ripe when it feels soft (as soft as a ripe avocado or a bit softer) and its skin has attained an amber to orange hue.

Papaya is native to Mexico and extends to South America and has become naturalized throughout the Caribbean Islands, Florida and several countries of Africa. Additional crops are grown in India, Australia, Malaysia, Indonesia, the Philippines, Thailand and the U.S. state of Hawaii.

Papaya plants grow in three sexes: male, female, hermaphrodite. The male produces only pollen, never fruit. The female will produce small, inedible fruits unless pollinated. The hermaphrodite can self-pollinate since its flowers contain both male stamens and female ovaries. Almost all commercial papaya orchards contain only hermaphrodites.

Originally from southern Mexico (particularly Chiapas and Veracruz), Central America, and northern South America, the papaya is now cultivated in most tropical countries. In cultivation, it grows rapidly, fruiting within three years. It is, however, highly frost-sensitive, limiting its production to tropical climates. Temperatures below −2 °C (29 °F) are greatly harmful if not fatal. In Florida and California, growth is generally limited to southern parts of the states. It prefers sandy, well-drained soil, as standing water will kill the plant within 24 hours.

For cultivation, however, only female plants are used, since they give off a single flower each time, and close to the base of the plant, while the male gives off multiple flowers in long stems, which result in poorer quality fruit.[clarification needed]