baking powder

American  

noun

1. any of various powders used as a substitute for yeast in baking, composed of sodium bicarbonate mixed with an acid substance, as cream of tartar, capable of setting carbon dioxide free when the mixture is moistened, causing the dough to rise.

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baking powder British  

noun

1. any of various powdered mixtures that contain sodium bicarbonate, starch (usually flour), and one or more slightly acidic compounds, such as cream of tartar: used in baking as a substitute for yeast

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baking powder Scientific  

/ bā′kĭng /

1. A mixture of baking soda, a nonreactive filler (such as starch), and at least one slightly acidic compound (such as cream of tartar). Baking powder works as a leavening agent in baking by releasing carbon dioxide when mixed with a liquid, such as milk or water.

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Etymology

Origin of baking powder

First recorded in 1840–50

Example Sentences

If the tech industry were a bakery, dysprosium would be like baking powder: It is used in small quantities but essential for enabling electric-car motors, wind turbines, military systems and computer-chip machinery.

From The Wall Street Journal • Oct. 11, 2025

The chocolate digestive was launched about a quarter of a century after the plain variety, whose name was inspired by the belief that the baking powder in the recipe would help with digestion.

From BBC • Apr. 24, 2025

With plenty of baking powder and nothing heavy like fruits or nuts in the batter, they have a great rise and puff up on top.

From Salon • Jan. 2, 2025

These appeared on every quick bread and muffin I baked, whether they used baking soda, baking powder or both.

From Seattle Times • Apr. 2, 2024

In the middle of the shelf, she grouped the baking powder, a box of salt, the mostly empty sack of flour, and the tin of lard.

From "Out of Darkness" by Ashley Hope Pérez