Etymology Borrowed from Middle French protocolle, protocole (“document, record”), from Late Latin protocollum (“the first sheet of a volume (on which contents and errata were written)”), from Byzantine Greek πρωτόκολλον (prōtókollon, “first sheet glued onto a manuscript”), from πρῶτος (prôtos, “first”) + κόλλα (kólla, “glue”).
Historical The minutes, or official record, of a negotiation or transaction; especially a document drawn up officially which forms the legal basis for subsequent agreements based on it.
Another account says that, on the morning of the 31st of May, the king delivered to the prince-royal the crown, the sceptre, and the key of his treasure and gave him his blessing. The privy-counsillor Vockerodt drew up at his desire a protocol of the transaction.1842, Thomas Campbell, Frederick the Great and his Times, volume II, page 47:
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Archaic An official record of a diplomatic meeting or negotiation; later specifically, a draft document setting out agreements to be signed into force by a subsequent formal treaty.
International law
The terms of this protocol formed the basis for the Treaty of London signed by the British, French and Russian governments on 6 July 1827.1970, Matthew Smith Anderson, The Great Powers and the Near East, 1774-1923, page 32:
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An amendment to an official treaty.
International law
The 1992 Protocol amended the definitions of other terms, including ‘ship’, ‘oil’ and ‘incident’: Art. 2.2002, Philippe Sands, Principles of International Environmental Law, p. 917 n. 253
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The first leaf of a roll of papyrus, or the official mark typically found on such a page.
They marked the beginning of each scroll with their protocol, a practice that continued in the papyrus trade in the Byzantine Empire [...] into the Islamic period, when there were bilingual protocols in Greek and Arabic.1991, Leila Avrin, Scribes, Script, and Books, page 146:
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The official formulas which appeared at the beginning or end of certain official documents such as charters, papal bulls etc.
The protocol of the bull contains elements that appear to be formulaic by the time of John XVIII 's pontificate.1985, Archivum Historiae Pontificiae, volume 23, page 14:
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Sciences The original notes of observations made during an experiment.
The following is an abstract of the protocol of the experiment: Tumour extract.—A measured 16 c.c. of minced Rous Sarcoma tissue was ground with sand and extracted with 400 c.c. of 0.8-per-cent. saline.1931, Gye & Purdy, The Cause of Cancer, page 194:
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Sciences The precise method for carrying out or reproducing a given experiment.
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The official rules and guidelines for heads of state and other dignitaries, governing accepted behaviour in relations with other diplomatic representatives or over affairs of state.
Even the Queen (for whom the curtsey is a more standard address) was recently treated to an enthusiastic Obama embrace. Her Majesty, who is not normally known for partaking in such public displays of affection, seemed unperturbed by Michelle Obama's disregard for royal protocol.2009 September 19, Laura Johnson, “A mwah too far”, in The Guardian:
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Broadly An accepted code of conduct; acceptable behaviour in a given situation or group.
For those uncertain in the protocol of handshaking a formula for the perfect handshake has been devised by scientists at the University of Manchester.2010 July 16, The Guardian:
TfW has staff enforcing mask protocols at all the busy stations and most travellers oblige, albeit some with ill grace.2020 December 2, Paul Bigland, “My weirdest and wackiest Rover yet”, in Rail, page 66:
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Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences A set of formal rules describing how to transmit or exchange data, especially across a network.
Moloch passed the message to the Behemoth / Whose master passed it on to Zebedee / It was sent by Internet, by obscure protocols / To its recipient, the delicious Miss Gee2001, “More Shopping”, in Discosis, performed by Bran Van 3000 ft. Momus:
An exception is Jabber, which is designed based on an open protocol called the extensible messaging and presence protocol (XMPP).2006, Zheng & Ni, Smart Phone and Next-Generation Mobile Computing, p. 444
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Founders of those kinds of platforms argue that they are just building a “protocol” ultimately led by a community of users, with the computer code effectively running the show.2021 September 5, Eric Lipton, Ephrat Livni, “Crypto’s Rapid Move Into Banking Elicits Alarm in Washington”, in The New York Times, →ISSN:
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Medicine, Sciences The set of instructions allowing a licensed medical professional to start, modify, or stop a medical or patient care order.
This protocol of the Preface has been constant, with minor modification, from the Apostolic Tradition, of Hippolytus in 215 A.D., the earliest extant text of the Eucharistic Prayer, to the present 2002 Missale Romanum.2010, Virgilio T.J. Suerte Felipe, The Lord’s Supper, Eucharist, Mass… What’s in a Name? […], →ISBN, pages 45–46:
The proper Preface for Eucharistic Prayer II also appears as Common Preface VI. In it, the protocol and body of the Preface structure are meshed.2011, Michael S. Driscoll, J. Michael Joncas, The Order of Mass: A Roman Missal Study Edition and Workbook, →ISBN, page 213:
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The celebrant then takes up this response in the first part of the preface itself (also known by the technical term ‘protocol’): […][2022, Uwe Michael Lang, The Roman Mass: From Early Christian Origins to Tridentine Reform, →ISBN, page 140:
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In some programming languages, a data type declaring a set of members that must be implemented by a class or other data type.
Etymology Borrowed from Middle French protocolle, protocole (“document, record”), from Late Latin protocollum (“the first sheet of a volume (on which contents and errata were written)”), from Byzantine Greek πρωτόκολλον (prōtókollon, “first sheet glued onto a manuscript”), from πρῶτος (prôtos, “first”) + κόλλα (kólla, “glue”).
Obsolete To make or write protocols, or first drafts; to issue protocols.
Serene Highnesses, who sit there protocolling and manifestoing, and consoling mankind!1837, Thomas Carlyle, chapter III, in The French Revolution: A History […], volume II (The Constitution), London: Chapman and Hall, →OCLC, book VI (The Marseillese), page 279: