Azadirachta indica, commonly known as neem, margosa, nimtree or Indian lilac,[3] is a tree in the mahogany family Meliaceae.

It is native to the Indian subcontinent and to parts of Southeast Asia, but is naturalized and grown around the world in tropical and subtropical areas.

[8] White and fragrant flowers are arranged in more-or-less drooping axillary panicles which are up to 25 cm (10 in) long.

The margosa tree[9] is similar in appearance to its relative, the chinaberry or bakain, Melia azedarach,[10] with which it may be confused.

[13] For both his species, Linnaeus referred to the name 'azedarach',[12] which is derived from the French 'azédarac', which in turn is from the Persian 'āzād dirakht' (ازادرخت), meaning 'free or noble tree'.

It can grow in regions with an annual rainfall below 400 mm, but in such cases it depends largely on ground water levels.

Margosa is one of very few shade-giving trees that thrive in drought-prone areas such as the dry coastal, southern districts of India and Pakistan.

In India and tropical countries where the Indian diaspora has reached, it is very common to see margosa trees used for shade lining streets, around temples, schools and other such public buildings or in most people's backyards.

[17] After being introduced into Australia, possibly in the 1940s, A. indica was originally planted in the Northern Territory to provide shade for cattle.

Trial plantations were established between the 1960s and 1980s in Darwin, Queensland, and Western Australia, but the Australian margosa industry did not prove viable.

In Bengal, young margosa leaves are fried in oil with tiny pieces of aubergine (brinjal).

Margosa is used in parts of mainland Southeast Asia, particularly in Cambodia, Laos (where it is called kadao [ກະເດົາ]), Thailand (where it is known as sadao [สะเดา [sàʔ daw] or satao สะเตา [sàʔ taw]]), Myanmar (where it is known as ta.ma [တမာ]) and Vietnam (where it is known as sầu đâu and is used to cook the salad gỏi sầu đâu).

In Myanmar, young margosa leaves and flower buds are boiled with tamarind fruit to soften its bitterness and eaten as a vegetable.

[23] Margosa is a key ingredient in non-pesticidal management (NPM), providing a natural alternative to synthetic pesticides.

[25] According to the American Journal of Neuroradiology, margosa oil has the ability to cause some forms of toxic encephalopathy and ophthalmopathy if consumed in quantities exceeding 150ml (5.07 us fluid ounces).

In 2000, the EPO ruled in India's favour, but W. R. Grace appealed, claiming that prior art about the product had never been published.

[19] Currently, the extraction process has disadvantages such as contamination with fungi and heterogeneity in the content of limonoids due to genetic, climatic, and geographical variations.

[38][39] To overcome these problems, production of limonoids from plant cell suspension and hairy root cultures in bioreactors has been studied,[40][41] including the development of a two-stage bioreactor process that enhances growth and production of limonoids with cell suspension cultures of A.