protocol

noun

pro·​to·​col ˈprō-tə-ˌkȯl 

-ˌkōl,

-ˌkäl,

-kəl

1

: an original draft, minute, or record of a document or transaction

2

a

: a preliminary memorandum often formulated and signed by diplomatic negotiators as a basis for a final convention or treaty

b

: the records or minutes of a diplomatic conference or congress that show officially the agreements arrived at by the negotiators

3

a

: a code prescribing strict adherence to correct etiquette and precedence (as in diplomatic exchange and in the military services)

a breach of protocol

b

: a set of conventions governing the treatment and especially the formatting of data in an electronic communications system

network protocols

c

: convention sense 3a,b

4

: a detailed plan of a scientific or medical experiment, treatment, or procedure

Did you know?

Protocol and Politics

In Late Greek, the word prōtokollon referred to the first sheet of a papyrus roll bearing the date of its manufacture. In some instances, it consisted of a flyleaf that was glued to the outside of a manuscript's case and provided a description of its contents. Coming from the Greek prefix prōto- ("first") and the noun kolla ("glue"), prōtokollon gave us our word protocol. In its earliest uses in the 15th century, the word referred to a prologue or preface and also to a record of a document or transaction. In the late 19th century, it began to be used in reference to the etiquette observed by the Head of State of France in ceremonies and relations with other dignitaries. This sense has since extended in meaning to cover any code of proper conduct.

Examples of protocol in a Sentence

Typically, those who make pronouncements like this assume (without saying so) that the tongues making up the multitude will belong to persons who are committed to the protocols of rational inquiry; frivolous persons, persons who exploit those protocols or play with them to gain political ends, are not imagined. —Stanley Fish, Harper's, December 2005

Purcell even flouted the timeless protocol of pretending to admire the work of his fellow editors. —Tobias Wolff, Old School, 2003

Today, thanks to the civil-rights movement, white guilt is propriety—an utterly invisible code that defines decency in our culture with thousands of little protocols we no longer even think about. —Shelby Steele, Harper's, November 2002

The soldier's actions constitute a breach of military protocol.

They did not follow the proper diplomatic protocols.

What is the proper protocol for declining a job offer?

the Geneva Protocol of 1925

Recent Examples on the Web

What the Socket Threat Research Team discovered, as reported by Olivia Brown, a threat analyst at Socket, is that attackers have created a bunch of malicious Python packages that use Gmail’s SMTP protocol to create a tunnel that can exfiltrate data and execute attack commands. —Davey Winder, Forbes.com, 3 May 2025

But each species seems to need its own cryopreservation protocol. —Katarina Zimmer, Smithsonian Magazine, 2 May 2025

Only a fraction of that system was going to be federally funded, and the office worked on making the whole network more reliable, with a focus on the technical standards and shared protocols that reduce glitches when cars and chargers interact. —Camila Domonoske, NPR, 1 May 2025

In January 2024, about 56 percent of driver's licenses and IDs in circulation nationwide complied with the new protocols, according to the Federal Register. —Nick Mordowanec, MSNBC Newsweek, 1 May 2025

Word History

Etymology

Middle French prothocole, from Medieval Latin protocollum, from Late Greek prōtokollon first sheet of a papyrus roll bearing date of manufacture, from Greek prōt- prot- + kollan to glue together, from kolla glue; perhaps akin to Middle Dutch helen to glue

First Known Use

1541, in the meaning defined at sense 1

Phrases Containing protocol

• hypertext transfer protocol

Rhymes for protocol

• aerosol
• alcohol
• arbitral
• basketball
• butanol
• cannonball
• carbinol
• catarrhal
• cortisol
• ethanol
• fireball
• gasohol

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Kids Definition

protocol

noun

pro·​to·​col ˈprōt-ə-ˌkȯl 

1

: an original copy or record of a document

2

: a code of diplomatic or military rules of behavior

3

: a set of rules for the formatting of data in an electronic communications system

network protocols

Medical Definition

protocol

noun

pro·​to·​col ˈprōt-ə-ˌkȯl, -ˌkōl, -ˌkäl 

1

: an official account of a proceeding

especially : the notes or records relating to a case, an experiment, or an autopsy

2

: a detailed plan of a scientific or medical experiment, treatment, or procedure

cryotherapy was performed in approximately half of the eyes through a randomization protocol

—The Journal of the American Medical Association

Legal Definition

protocol

noun

pro·​to·​col ˈprō-tə-ˌkȯl 

1

: an original draft, minute, or record of a document or transaction

2

a

: a preliminary memorandum often formulated and signed by diplomatic negotiators as a basis for a final convention or treaty

b

: the records or minutes of a diplomatic conference or congress that show officially the agreements arrived at by the negotiators