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pro·to·col (prōtə-kôl′, -kōl′, -kŏl′)
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n.
1.
a. The forms of ceremony and etiquette observed by diplomats and heads of state.
b. A code of correct conduct: safety protocols; academic protocol.
2. The first copy of a treaty or other such document before its ratification.
3. A preliminary draft or record of a transaction.
4. The plan for a course of medical treatment or for a scientific experiment.
5. Computers A standard procedure for regulating data transmission between computers.
intr.v. pro·to·coled, pro·to·col·ing, pro·to·cols or pro·to·colled or pro·to·col·ling
To form or issue protocols.
[French protocole, from Old French prothocolle, draft of a document, from Medieval Latin prōtocollum, from Late Greek prōtokollon, table of contents, first sheet : Greek prōto-, proto- + Greek kollēma, sheets of a papyrus glued together (from kollān, to glue together, from kolla, glue).]
proto·col′ar (-kŏlər), pro′to·cola·ry (-kŏlə-rē) 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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