pro·​to·​plasm | \ ˈprō-tə-ˌpla-zəm \

Definition of protoplasm

1 : the organized colloidal complex of organic and inorganic substances (such as proteins and water) that constitutes the living nucleus, cytoplasm, plastids, and mitochondria of the cell
2 : cytoplasm

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Other Words from protoplasm

protoplasmic \ ˌprō-​tə-​ˈplaz-​mik \ adjective

Did You Know?

After the word protoplasm was coined in the mid-19th century for the jellylike material that is the main substance of a cell, it began to be used widely, especially by scientists and others who imagined that the first life-forms must have arisen out of a great seething protoplasmic soup. Since protoplasm includes all the cell's living material, inside and outside the nucleus, it is a less useful scientific word today than more precise terms such as cytoplasm, which refers only to the living material outside the nucleus. But many remain fascinated by the image of that soup bubbling away as the lightning flashes and the volcanoes erupt.

Examples of protoplasm in a Sentence

Recent Examples on the Web

Altmann believed that cells themselves came into existence when these granules assembled into colonies and built a shelter of protoplasm around themselves. Carl Zimmer, STAT, "Shot through with microbes: How our bodies adapt to a hidden world of bacteria," 30 May 2018 Responding to a moldy sack of protoplasm who writes for the Daily Caller, CNN editor Chris Cillizza leapt to Jacobs’s defense. Brian Beutler, New Republic, "The Republicans Broke American Politics, and Media Elites Are Blind to It," 26 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'protoplasm.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of protoplasm

1848, in the meaning defined at sense 1

History and Etymology for protoplasm

German Protoplasma, from prot- + New Latin plasma

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The first known use of protoplasm was in 1848

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English Language Learners Definition of protoplasm

biology : the usually colorless substance that is the living part of animal and plant cells


pro·​to·​plasm | \ ˈprō-tə-ˌpla-zəm \

Kids Definition of protoplasm

: the usually colorless and jellylike living part of cells


pro·​to·​plasm | \ ˈprōt-ə-ˌplaz-əm \

Medical Definition of protoplasm

1 : the organized colloidal complex of organic and inorganic substances (as proteins and water) that constitutes the living nucleus, cytoplasm, plastids, and mitochondria of the cell and is regarded as the only form of matter in which the vital phenomena (as metabolism and reproduction) are manifested
2 : cytoplasm

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More from Merriam-Webster on protoplasm

Rhyming Dictionary: Words that rhyme with protoplasm

Spanish Central: Translation of protoplasm

Nglish: Translation of protoplasm for Spanish Speakers Encyclopedia article about protoplasm

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someone who never drinks alcohol

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