Solanum aethiopicum, the bitter tomato, Ethiopian eggplant, or nakati, is a fruiting plant of the genus Solanum mainly found in Asia and Tropical Africa. It is also known as Ethiopian nightshade, garden eggs, pumpkin-on-a-stick, and mock tomato. It is a popular vegetable in north-east India, and is known as khamen akhaba in Manipuri and samṭawk in Mizo. They are called Titay bii or simply bii in Darjeeling, Sikkim and Nepal and are relished with meat, particularly pork. These names are a result of its varied morphology, with ripe fruit often looking like a cross between an eggplant and a tomato, which are also from Solanum. In fact, the Ethiopian eggplant was so much confused with the ordinary eggplant that this was considered by some a variety violaceum of S. aethiopicum.

Solanum is a large and diverse genus of flowering plants, which include three food crops of high economic importance: the potato, the tomato and the eggplant. It is the largest genus in the nightshade family Solanaceae, comprising around 1,500 species. It also contains the so-called horse nettles, as well as numerous plants cultivated for their ornamental flowers and fruit.