The plant genus containing banana plants, including dessert bananas and plantains, is Musa.
Musa is a genus of large flowering plants in the banana family, Musaceae. Its species are native mainly to tropical and subtropical regions of Asia, Australia, and Africa. Commercial bananas are usually seedless hybrids, especially cultivars derived from Musa acuminata and Musa balbisiana.
Although banana plants look like trees, they are giant herbs. Their apparent trunk is a pseudostem formed from tightly packed leaf bases, and the plant grows from an underground corm. After flowering and fruiting, that pseudostem usually dies and is replaced by shoots from the corm.
Plantains are also members of Musa, but the word “banana” can refer to many different cultivars and species. Ensete is a related genus sometimes called false banana, but it is not the genus containing ordinary cultivated bananas.