The name "Toronto" has a rich history, with various spellings recorded in French and English, including Tarento, Tarontha, Taronto, Toranto, Torento, and Toronton. The earliest common spelling, Taronto, referred to a geographical feature known as "The Narrows"—a water channel through which Lake Simcoe flows into Lake Couchiching. The Huron people used this area to plant tree saplings to corral fish. The Mohawk people referred to this location as tkaronto, meaning "where there are trees standing in the water." This term was first recorded by Samuel de Champlain in 1615.

In addition to this geographical meaning, the word Toronto also appears in a 1632 French lexicon of the Huron language, an Iroquoian language, where it is interpreted to mean "plenty." Early French maps also used the name Toronto to refer to various locations, including Georgian Bay, Lake Simcoe, and nearby rivers. The well-known Toronto Carrying-Place Trail, a portage route connecting Lake Ontario to Lake Huron, helped cement the widespread use of the name.

The pronunciation of Toronto is commonly /təˈrɒntoʊ/ (tə-RONT-oh), though locals often pronounce it [təˈɹɒnoʊ] or [ˈtɹɒnoʊ], dropping the second "t." The city's name, deeply tied to its Indigenous roots, continues to reflect the area’s cultural significance and rich history.