Although the latter common usage apparently developed later,[3] the root meaning had existed for centuries.

[4] The Lardeau spelling suggests a French influence, but the geographical word origin probably had more to do with lard or bacon.

In 1893, the land registry initially refused to accept the Lardo townsite plan, because the name was too similar to Lardeau.

In reality, most residents of the Upper Arrow Lake area would have preferred their part of the valley not be called the Lardeau mining district.

[6] In 1902, the Geographic Board of Canada approved the uniform spelling of Lardo as Lardeau.