Other forms: protocols
A protocol is a set of rules agreed in advance so that two sides can deal with each other without confusion. In computing it is what lets two machines talk: HTTP carries web pages between them, and the s in https marks a protocol that encrypts what passes.
Outside the server room, protocol is the rulebook of official manners — who is greeted first, who sits where, what a president is called. 'Protocol demands that the ambassador arrives last.' In hospitals and laboratories a protocol is the written procedure for a treatment or an experiment, followed step by step so that two sets of results can be compared. In diplomacy a protocol is a formal document as well, which is why treaties have protocols attached to them: the Kyoto Protocol, the Montreal Protocol. Watch the article — you follow a protocol in the computing and medical senses, but the etiquette sense goes bare: you follow protocol, you breach protocol.
1nounprotocolAn agreed set of rules that lets computers or devices exchange information.
“The camera talks to the app over a protocol designed for low-power devices.”
2nouncorrectThe rules of correct behaviour on official occasions.
“Nobody sits down before the guest of honour; that is basic protocol.”
3nounprocedureA written procedure for a medical treatment or a scientific experiment.
“Every nurse on the ward follows the same protocol for changing a dressing.”
4nouninternationalA formal international agreement, often one added to an existing treaty.
“The protocol was signed by more than a hundred countries.”
The Greek is protos, first, and kolla, glue: the first page glued to the front of a book, saying how to read what follows. A protocol still says how the thing is to be done.
hooks ontoglue
Protocol traces back to Greek protokollon, the first sheet glued onto a manuscript, from protos, first, and kolla, glue. That front sheet carried the contents and the corrections, so it became the page that told you what the document was. Latin took it as protocollum and French as protocole, meaning a record; from records came official form, and from official form came the rules two computers follow.
Medieval Greek
πρωτόκολλον — first sheet glued onto a manuscript
Latin
protocollum — the first sheet of a volume (on which contents and errata were written)
Middle French
protocolle, protocole — document, record
English, today
protocol
Built from
Borrowed from Middle French protocolle, protocole (“document, record”), from Latin protocollum (“the first sheet of a volume (on which contents and errata were written)”), from Medieval Greek πρωτόκολλον (“first sheet glued onto a manuscript”), from πρῶτος (“first”) + κόλλα (“glue”).
Etymology from Wiktionary, CC BY-SA
Practised in Computing & Code, Manners & Etiquette