chlorophyll

noun

1
: the green photosynthetic pigment found chiefly in the chloroplasts of plants and occurring especially as a blue-black ester C55H72MgN4O5 or a dark green ester C55H70MgN4O6

called also respectively chlorophyll a, chlorophyll b

2
: a waxy green chlorophyll-containing substance extracted from green plants and used as a coloring agent or deodorant

Examples of chlorophyll in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Across the country, trees and shrubs shut down the production of their energy-making chlorophyll, the pigment behind their lush greens, leaving behind vivid forests of yellows, oranges and reds. — Jeanne Bonner, CNN Money, 7 Oct. 2026 Depriving the plant of light discourages the development of chlorophyll—the green plant pigment responsible for color—and rids the chicory of an unpleasant flavor. — Tamar Adler, Vogue, 29 Sep. 2026 Nitrogen is also a core component of chlorophyll, which absorbs energy from light in photosynthetic organisms, and adenosine triphosphate (ATP), the primary energy-carrying molecule found in the cells of plants and animals. — Encyclopedia Britannica, 9 Sep. 2026 The moderating influence of the surrounding Great Lakes often keeps coastal and southern areas warmer, delaying the seasonal breakdown of chlorophyll that reveals the classic yellows, oranges and reds. — Ahmad Bajjey, CBS News, 9 Sep. 2026 See All Example Sentences for chlorophyll

Word History

Etymology

French chlorophylle, from chlor- + Greek phyllon leaf — more at blade

First Known Use

1819, in the meaning defined at sense 1

Time Traveler
The first known use of chlorophyll was in 1819

Browse Nearby Words

Cite this Entry

“Chlorophyll.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chlorophyll. Accessed 9 Oct. 2026.

Kids Definition

chlorophyll

noun
chlo·​ro·​phyll ˈklōr-ə-ˌfil How to pronounce chlorophyll (audio)
ˈklȯr-, 
-fəl
: the green coloring matter that is found chiefly in the chloroplasts of plants and is necessary for photosynthesis

Medical Definition

1
: the green photosynthetic coloring matter of plants found in chloroplasts and made up chiefly of a blue-black ester C55H72MgN4O5 and a dark green ester C55H70MgN4O6

called also respectively chlorophyll a, chlorophyll b

2
: a waxy green chlorophyll-containing substance extracted from green plants and used as a coloring agent or deodorant

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