Wordorigins.org

The peninsula of Labrador is the mainland component of the Canadian province of Newfoundland and Labrador. The name is from the Portuguese lavrador, meaning a small landowner.

In 1500, Portuguese explorer João Fernandes, a lavrador, designated the island of Greenland as Tiera del Lavrador and named the current peninsula of Labrador Tiera del Corte-Real, after Gaspar Corte-Real. But by 1560, Portuguese mapmakers gave way to the wider convention and started calling Greenland by that name and shifted the name Tiera del Lavrador to the Labrador peninsula and the name stuck.

Labrador retrievers are named after the province, where the breed originated.

(Source: Dictionary of Canadian Place Names)