Webster's Revised Unabridged Dictionary · 1913

Mackinaw

Mackinaw

A flat-bottomed boat with a pointed prow and square stern, using oars or sails or both, used esp. on the upper Great Lakes and their tributaries.

Also: Mackinaw boat

Mackinaw

A short, heavy, double-breasted plaid coat, the design of which is large and striking. [Local, United States]

Also: Mackinaw coat