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plas·ma (plăzmə)
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n. also plasm (plăzəm)
1.
a. The clear, yellowish fluid portion of blood, lymph, or intramuscular fluid in which cells are suspended. It differs from serum in that it contains fibrin and other soluble clotting elements.
b. Blood plasma, especially when sterilized and depleted of cells for transfusion.
2. Protoplasm or cytoplasm.
3. The fluid portion of milk from which the curd has been separated by coagulation; whey.
4. Physics An electrically neutral, highly ionized phase of matter composed of ions, electrons, and neutral particles. It is distinct from solids, liquids, and gases.
adj.
Of or relating to a flat-panel display used in televisions, made up of an array of tiny cells each containing a gaseous mixture of xenon and neon that is changed into a plasma state to illuminate a phosphor coating on the inside of the cell.
[New Latin, from Late Latin, image, figure, from Greek, from plassein, to mold; see pelə-2 in the Appendix of Indo-European roots.]
plas·matic (plăz-mătĭk), plasmic (-mĭk) adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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