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definitions

frosting

[fraw-sting, fros-ting]
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noun

a sweet mixture, cooked or uncooked, for coating or filling cakes, cookies, and the like; icing.
a dull or lusterless finish, as on metal or glass.
a process of highlighting the hair by bleaching selected strands.
a material used for decorative work, as signs, displays, etc., made from coarse flakes of powdered glass.

Idioms

    the frosting on the cake, something added to make a thing better or more desirable.Also icing on the cake.

Origin of frosting

First recorded in 1610–20; frost + -ing1
Related formsnon·frost·ing, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for frosting on the cake

frosting

noun

a soft icing based on sugar and egg whites
Also called: icing a sugar preparation, variously flavoured and coloured, for coating and decorating cakes, biscuits, etc
a rough or matt finish on glass, silver, etc
slang the practice of stealing a car while the owner has left it idling to defrost the windows and heat the engine
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for frosting on the cake

frosting

n.

1610s as an action; 1756 as a substance; meaning "cake icing" is from 1858; verbal noun from frost (v.).

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with frosting on the cake

frosting on the cake

see icing on the cake.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.