TOS

TOS may refer to:

General

Terms of service, rules by which one must agree to abide by in order to use a service; unless in violation of consumer protection laws, such terms are usually legally binding

Tosyl, a chemical group
TOS, an abbreviation for Gy's sampling theory, a theory about the sampling of materials

Title of show, a Broadway musical
Star Trek: The Original Series, a 1960s science fiction television series
Battlestar Galactica (1978 TV series), a 1970s science fiction television series
The Objective Standard, an American journal on culture and politics written from the Objectivist perspective
T.O.S: Terminate on Sight, a 2008 album by G-Unit
Tree of Savior, a free massively multiplayer online role playing game developed by IMC Games

Thoracic outlet syndrome, a syndrome involving compression of the superior thoracic outlet, leading to the compression of the neurovascular bundle passing between the anterior scalene and middle scalene
Toxic oil syndrome, a disease outbreak in Spain in 1981 which killed over 600 people

The Oceanography Society, a non-profit society founded in 1988, based in Rockville, Maryland, U.S. and incorporated in the District of Columbia
Theosophical Order of Service, an international organization founded in 1908 by Annie Besant, the second International President of the Theosophical Society
Temple of Set, an initiatory occult society claiming to be the world's leading left-hand path religious organization; it professes Setian philosophy and magical practice
Tennessee Ornithological Society
Trucial Oman Scouts, a paramilitary force that the British raised in 1951 as the Trucial Oman Levies, to serve in the Trucial States

TOS-1, a Soviet thermobaric weapon system nicknamed 'Buratino'
Tam o' Shanter (cap), a Scottish bonnet, worn in place of a beret by certain military units
Atari TOS, an operating system of the Atari ST range of computers
TOS/360, Tape Operating System/360
Tornado outbreak sequence, an extended period of high tornadic activity in which nearly every day there is significant tornado activity (multiple unbroken outbreaks)
Tromsø Airport, in the northern city of Tromsø, Norway
Television Oita, a television station in Oita, Oita Prefecture, Japan
Type of service, a field in the header of IPv4 packets
Terminal Operating System, a system controls the movement and storage of various types of Cargo in and around a container terminal or port