marshmallow

noun

marsh·​mal·​low ˈmärsh-ˌme-lō 

-ˌma-

1

usually marsh mallow : a pink-flowered European perennial herb (Althaea officinalis) of the mallow family that is naturalized in the eastern U.S. and has flowers, leaves, and roots used in herbal remedies

2

: a sweet white confection usually in the form of a spread or small spongy cylindrical pieces now usually made from corn syrup, sugar, albumen, and gelatin but formerly from the marshmallow's root

also : one of these spongy pieces

toasted marshmallows on sticks over a campfire

marshmallowy

ˈmärsh-ˌme-lə-wē 

-ˌma-

adjective

Examples of marshmallow in a Sentence

We toasted marshmallows over the fire.

Recent Examples on the Web

One of my favorite memories is watching my abuela's face as my cousin's marshmallow caught fire. —Annabelle Canela, Parents, 14 Aug. 2025

Unlike the unbaked marshmallow treats counterpart, the marshmallow bits in these cookies get a chance to bake and caramelize in the oven's heat, turning them even more chewy. —Kimberly Holland, Southern Living, 23 July 2025

The marshmallow cookies join a grocery list of other Costco items released this summer, including the Kirkland Signature Peaches and Cream Bar Cake and the frozen strawberry lemonade. —Deirdre Bardolf, FOXNews.com, 22 July 2025

Toasty graham crackers and roasted marshmallows balance the overall sweetness, while melted butter and gooey marshmallows soften the dry graham crackers and brittle chocolate. —The New York Times News Service Syndicate, San Diego Union-Tribune, 16 July 2025

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1

Rhymes for marshmallow

• morello
• othello
• schoolfellow
• cello
• fellow
• jello
• mellow
• melo
• velo
• portobello
• violoncello

Kids Definition

marshmallow

noun

marsh·​mal·​low ˈmärsh-ˌmel-ō 

-ˌmal-

1

: a pink-flowered herb related to the mallows that has a root sometimes used in sweets and in medicine

2

: a soft spongy sweet formerly made from the root of the marshmallow but now usually prepared from corn syrup, sugar, albumen, and gelatin

Medical Definition

marshmallow

noun

marsh·​mal·​low ˈmärsh-ˌmel-ō, -ˌmel-ə(-w), -ˌmal- 

: a European perennial herb of the genus Althaea (A. officinalis) naturalized in the eastern United States whose pink flowers, velvety leaves, and mucilaginous root are used in herbal medicine and whose root was formerly used in confectionary see althaea sense 2