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

Their chlorophyll content supports oxygenation and liver function. —Mélanie Defouilloy, Vogue, 24 Feb. 2026

After the storm, this surface layer helped spread chlorophyll sideways, fueling an algae bloom visible from space. —Neetika Walter, Interesting Engineering, 23 Feb. 2026

This is because plants require light to carry out the essential process of photosynthesis, which involves chlorophyll absorbing light to produce energy (sugars) for growth. —Gemma Johnstone, The Spruce, 8 Feb. 2026

Water-soluble chlorophyll, which gives broccoli its signature color, is vulnerable to degradation during prolonged cooking or boiling. —Anne Wolf, Martha Stewart, 7 Feb. 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