Word of the Day


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Liz Potter
Written by Liz Potter


1. a set of rules for the correct way to behave on formal occasions

2. a set of rules for the correct way to provide a medical treatment or do a scientific experiment

3. a set of rules that controls the ways in which data is sent between computers

View the full definition in the Macmillan Dictionary.

Origin and usage

The noun protocol came into English in the 16th century from the Old French word ‘prothocole’. It derives ultimately from  a Greek word ‘prōtokollon’ meaning first page, a combination of the words for ‘first’ and ‘glue’. The first meaning above was borrowed directly from ‘protocole’, the French word for the diplomatic rules of conduct, in the late 19th century.


Protocol has a number of different meanings, most of them relating to the rules for doing something. In computing, for example, a protocol is a set of rules that controls the ways in which data is sent between computers, essential for ensuring that systems work effectively. So WAP or Wireless Application Protocol is a standard for accessing information over a wireless network, while HTTP or HyperText Transfer Protocol defines how messages are formatted and transmitted via the internet. In medicine and science, a protocol is a set of rules governing the way a medical treatment is provided or an experiment is carried out. In a diplomatic context, protocol is the set of rules, generally unwritten, that govern how people are expected to behave in a given situation or in relation to a particular person. This kind of protocol has developed over the centuries to smooth international and internal relations and reduce the possibility of upsets and misunderstandings.


“I’m not a protocol fetishist. It’s more important to me that people feel at ease when I’m with them.”
(Willem-Alexander, King of the Netherlands)

“Anyone who considers protocol unimportant has never dealt with a cat.”
(Robert A Heinlein)

Related words

convention, etiquette, code

Browse related words in the Macmillan Thesaurus.

About the author

Liz Potter

Liz Potter

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