1. What does TOS stand for when using online services?

Terms of service

A provider's terms of service, also known as "terms of use," are conditions users must agree to in order to use the service. These conditions govern what users can and can't do when using the service. The terms may also explain what the service provider can do with users' data.

For example, streaming platform Twitch has a TOS that restricts what content streamers can share on their channels. One rule in Twitch's TOS prevents streamers from playing copyright-protected music on their channels, to ensure Twitch cannot be sued by musicians and record companies.

Every large online service provider, including Google, Twitter, Facebook, and Amazon, has its own TOS (or ToS). Many websites require you to agree to the terms of service, often by checking a box next to the TOS link, when creating an account.


Would streaming my workday violate Twitch's TOS?
Probably not, but would anyone watch that?
Apparently, sleeping streams do not violate the Twitch TOS
Apparently, sleeping streams do not violate the Twitch TOS

Related Slang


Updated February 24, 2021
2. What does TOS stand for among Star Trek fans?

The Original Series

Trekkies and other nerds use TOS to refer to Star Trek: The Original Series. The original Star Trek ran from 1966 to 1969 before being canceled by NBC.

Ahead of its time in more ways than one, Star Trek told the story of Captain Kirk and the crew of the starship Enterprise. Their five-year mission was to explore strange new worlds, seek out new life and new civilizations, and boldly go where no man has gone before.

While Kirk and crew did not get to finish their mission on-screen, Star Trek became a hit in syndication. Eventually, it spawned a plethora of movies and spin-offs. Arguably the most popular of those spin-offs was Star Trek: The Next Generation, which is sometimes referred to by the acronym TNG.


Which series did you like better - Star Trek TOS or TNG?

An amusing scene from TOS's The Trouble with Tribbles episode

Related Slang


Updated April 12, 2022

TOS definition by

This page explains what the acronym "TOS" means. The various definitions, examples, and related terms listed above have been written and compiled by the team.

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