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trans·form (trăns-fôrm)
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v. trans·formed, trans·form·ing, trans·forms
v.tr.
1. To change markedly the appearance or form of: "A thick, fibrous fog had transformed the trees into ghosts and the streetlights into soft, haloed moons" (David Michael Kaplan).
2. To change the nature, function, or condition of; convert: A steam engine transforms heat into mechanical energy. See Synonyms at convert.
3. Mathematics To subject to a transformation.
4. Electricity To subject to the action of a transformer.
5. Genetics To subject (a cell) to transformation.
v.intr.
To undergo a transformation.
n. (trănsfôrm)
The result, especially a mathematical quantity or linguistic construction, of a transformation.

[Middle English transformen, from Old French transformer, from Latin trānsfōrmāre : trāns-, trans- + fōrma, form.]

trans·forma·ble 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.