Merriam-Webster Collegiate Dictionary - toboggan

 I. noun  Etymology: Canadian French tobogan, of Algonquian origin; akin to Micmac tobagun drag made of skin  Date: circa 1820  1. a long flat-bottomed light sled made usually of thin boards curved up at one end with usually low handrails at the sides  2. a downward course or a sharp decline  3. chiefly Southern & Midland stocking cap  II. intransitive verb  Date: 1846  1. to coast on or as if on a ~  2. to decline suddenly and sharply  • ~er noun  • ~ist noun