arm of the Atlantic Ocean between Baffin Island ( Nunavut) and northern Quebec, Canada, linking Hudson Bay and Foxe Basin with the Labrador Sea. It is about 500 miles (800 km) long and 40–150 miles (65–240 km) wide and has a maximum depth of 3,090 feet (942 metres). Salisbury and Nottingham islands are at its entrance from the Foxe Channel (northwest) and Hudson Bay (southwest), and Resolution and Edgell islands are at its eastern entrance from the Labrador Sea.

The Hudson Strait is navigable only during late summer and early autumn, but icebreakers make the passage most of the year. It was partly explored in 1578 by Sir Martin Frobisher (Frobisher, Sir Martin), the English navigator. After it was fully navigated by the English explorer Henry Hudson (Hudson, Henry) in 1610, it became a main route for the ships of the Hudson's Bay Company.