mashed potatoes

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun plural Potatoes that are boiled and mashed, often with milk and butter.

from the GNU version of the Collaborative International Dictionary of English.

• noun plural Potatoes which have been boiled and mashed to a pulpy consistency, usu. with sparing addition of milk, salt, butter, or other flavoring. It is a popular accompaniment to a meat course [U.S., 1900's], providing bulk and calories to a meal.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun uncountable Potatoes that have been boiled and mashed to a pulpy consistency.
• noun Plural form of mashed potato.
• noun skiing Partially melted snow with a pulpy texture, making for slow skiing.