A mackinaw is a thick, heavy wool coat designed to keep you warm in bitter cold weather. The original mackinaws were short jackets made from thick wool blankets, often in bold plaid patterns of red, black, or green. Lumberjacks in the northern forests wore them while felling trees in freezing temperatures. Sailors on the Great Lakes relied on them to block icy winds that swept across the water.

The coat gets its name from Mackinaw City, Michigan, a town where the straits between Lake Michigan and Lake Huron create some of the coldest, windiest conditions imaginable. In the 1800s, traders there sold these sturdy wool coats to people who needed serious protection from winter.

A good mackinaw could last for years, even decades. The thick wool stayed warm even when wet, which mattered if you were working outdoors all day in snow and sleet. Today, people still wear mackinaws for outdoor work, hunting, or simply braving a harsh winter. When someone pulls on a mackinaw, they're wearing the same basic design that kept people warm over a century ago, built for the kind of cold that demands respect.