multicellular

American  

[muhl-tee-sel-yuh-ler, muhl-tahy-] / ˌmʌl tiˈsɛl yə lər, ˌmʌl taɪ- /

adjective

1. composed of several or many cells.

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multicellular Scientific  

/ mŭl′tē-sĕl′yə-lər /

1. Having or consisting of many cells.

2. Compare unicellular

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Etymology

Origin of multicellular

First recorded in 1855–60; multi- + cellular

Explanation

Something that's multicellular is a complex organism, made up of many cells. Humans are multicellular. While single-celled organisms can't usually be seen without a microscope, you can see most multicelluar organisms with the naked eye. Plants and animals are multicellular — although they all, including humans, start as a single cell that reproduces into many. Multi means "many," and the Latin root of cellular is cellularis, "of little cells," from cella, "small room."

Example Sentences

The rocks dated to the Ediacaran Period, which lasted from about 635 million to 541 million years ago, just before the Cambrian Period when complex multicellular life rapidly diversified.

From Science Daily • Feb. 27, 2026

Though Jablonski is more bullish on the survival prospects of unicellular life, there is some comfort for the multicellular among us too.

From Salon • Feb. 25, 2025

By the beginning of the Cambrian explosion of multicellular organisms about 540 million years ago, the ancestors of today’s ecdysozoans were already alive and varied in form and behavior, suggesting they arose even earlier.

From Science Magazine • Nov. 20, 2024

Rose disagrees with this hypothesis and points to the existence of multicellular animals, which have the same basic cell biology as humans, that don’t age at all.

From Salon • Oct. 12, 2024

Gene replication must explain how a multicellular organism emerges from a single cell—and errors in replication might elucidate how a spontaneous metabolic illness, or a devastating mental disease, might arise in a previously unaffected family.

From "The Gene" by Siddhartha Mukherjee