The name Solanaceae derives from the genus Solanum, "the nightshade plant". The etymology of the Latin word is unclear. The name may come from a perceived resemblance of certain solanaceous flowers to the sun and its rays. At least one species of Solanum is known as the "sunberry". Alternatively, the name could originate from the Latin verb solare, meaning "to soothe", presumably referring to the soothing pharmacological properties of some of the psychoactivespecies of the family.
The family has a worldwide distribution, being present on all continents except Antarctica. The greatest diversity in species is found in South America and Central America. In 2017, scientists reported on their discovery and analysis of a fossil tomatillo found in the Patagonian region of Argentina, dated to 52 million years B.P. The finding has pushed back the earliest appearance of the plant family Solanaceae. As tomatillos likely developed later than other nightshades, this may mean that the Solanaceae may have first developed during the Mesozoic Era.
The Solanaceae include a number of commonly collected or cultivated species. The most economically important genus of the family is Solanum, which contains the potato (S. tuberosum, in fact, another common name of the family is the "potato family"), the tomato (S. lycopersicum), and the eggplant or aubergine (S. melongena). Another important genus, Capsicum, produces both chili peppers and bell peppers.