The pistachio, a member of the cashew family, is a small tree originating in Persia. The tree produces seeds that are widely consumed as food. The word can be countable or uncountable, meaning its plural is with or without an 's'.

David Grandison Fairchild was an American botanist and plant explorer. Fairchild was responsible for the introduction of more than 200,000 exotic plants and varieties of established crops into the United States, including soybeans, pistachios, mangos, nectarines, dates, bamboos, and flowering cherries. Certain varieties of wheat, cotton, and rice became especially economically important.