chlorophyll

noun

chlo·​ro·​phyll ˈklȯr-ə-ˌfil 

-fəl

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

chlorophyllous

ˌklȯr-ə-ˈfi-ləs 

adjective

Examples of chlorophyll in a Sentence

Recent Examples on the Web

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

According to Wilkins Bratcher, plants that are deficient in magnesium may show signs of yellowing in their lower, older leaves and have a general lack of vitality because magnesium is the central element of the chlorophyll molecule. — Nadia Hassani, The Spruce, 7 Sep. 2026

That light exposure triggers the production of chlorophyll in the potato’s skin (the same pigment responsible for turning leaves green). — Anne Wolf, Martha Stewart, 29 Aug. 2026

Word History

Etymology

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

First Known Use

1819, in the meaning defined at sense 1

Kids Definition

chlorophyll

noun

chlo·​ro·​phyll ˈklōr-ə-ˌfil 

ˈklȯr-, 

-fəl

: the green coloring matter that is found chiefly in the chloroplasts of plants and is necessary for photosynthesis

Medical Definition

chlorophyll

noun

chlo·​ro·​phyll ˈklōr-ə-ˌfil, ˈklȯr-, -fəl 

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

chlorophyllous

ˌklōr-ə-ˈfil-əs, ˌklȯr- 

adjective

also chlorophyllose

-ˈfil-ˌōs, -(ˌ)fil-ˈ