Question: Define what a triskelion is.
About the article "Football", section "Based on FA rules".

Candidate passages:
 ""Triskellion" redirects here.
For the book series, see Triskellion (series)."
A triskelion or triskele (which invariably has rotational symmetry) is a motif consisting of three interlocked spirals, or three bent human legs.
Both words are from Greek ("triskelion") or ("triskeles"), "three-legged", from prefix "τρι-" ("tri-"), "three times" + "σκέλος" ("skelos"), "leg".
Although it appears in many places and periods, it is especially characteristic of the Celtic art of the La Tène culture of the European Iron Age.
A triskelion is the symbol of Sicily, where it is called "trinacria", as well as of the Isle of Man, Brittany, and the town of Füssen in Germany. 
Triskelion Arts is a non-profit arts presenting organization which includes two theaters and rehearsal studios in Williamsburg, Brooklyn.
The performance art space began in 2000 and was conceived by the collective, KICK STAND DANCE.
In 2005, one of its founders, Abby Bender, and colleague Andy Dickerson succeeded the collective and have operated the organization ever since.
Under their direction, Triskelion Arts has grown from one studio/theater to five spaces, and is a place “where young companies can afford to self-produce and where choreographers can take a chance.” Since 2000, Triskelion Arts has presented 500 companies, including Peter Kyle Dance, Stefanie Nelson Dancegroup, Cirque This, Jessica Gaynor Dance, Shannon Gillen & Guests, to name a few. 
A triskelion is featured on the seal of the United States Department of Transportation.
A triskelion shape is the basis for the roundel of the Irish Air Corps, and the logo for the GNU/Linux distribution Trisquel.
A triskelion shape was used in the design of RCA's "Spider" 45 rpm adapter, a popular plastic adapter for vinyl records, which allows larger center-holed 45 rpm records (commonly used on 7" singles and EPs) to spin on players designed for smaller center-holed 33-1/3 rpm records (the standard for 10" and 12" LPs).
The design was practical, the three curved arms providing equal spring and thus keeping the hole centred.
The iconic design of the Spider has led to its adoption as a popular symbol for record and music enthusiasts.
A triskelion is used as the badge of the Victoria Highlanders FC, a Canadian soccer team based in Victoria, British Columbia, Canada.
One of the most commonly used symbols of the BDSM community is a derivation of a triskelion shape within a circle.
The crest of the Breton football club En Avant de Guingamp combines the Flag of Brittany, the team colours and the triple spiral triskelion.
A design based on the Korean Sam Taegeuk was incorporated into the logo for the 1988 Summer Olympics in Seoul.
Razer Inc, a company that produces computer components for gamers, uses a triskelion logo in the form of snakes.
The Triskelion is a symbol of the Hale family of werewolves in the MTV show Teen Wolf. 
The escutcheon is emblazoned: "Gules a triskele argent garnished and spurred Or".
The triskele (or triskelion) is an ancient symbol, consisting of three branches or legs, that radiate from a centre.
The symbol is found on the flag Isle of Man, and earlier on that of Sicily.
The Manx triskelion is known in the Manx language as "Ny Tree Cassyn" ("The Three Legs").
The symbol has been associated with the island since at least the 13th century.
It is unknown how the Manx triskelion was originally adopted, and several theories have been put forward its origin.
In 1607, English historian William Camden stated that it was derived from the Sicilian triskelion.
In 1885 John Newton considered the Manx triskelion originated in the mid 13th century, when the Pope offered the throne of Sicily to Edmund, son of King Henry III of England.
Newton noted that the wife of King Alexander III of Scotland was Henry's daughter, and that Alexander visited the English court in 1255.
Later in 1266, Norway ceded the Isle of Man to the Kingdom of Scotland, and Newton considered it likely that Alexander utilised the triskelion for the arms of his new possession.
It has also been suggested that the ancestry of the Manx triskelion can be traced to the triquetra in a coin of Olaf Cuaran, a 10th-century Norse-Gaelic warlord who was king of Northumbria and king of Dublin.
Lending credibility to this theory is the current belief that the mediaeval Manx dynasty was related to that of Olaf Cuaran.
However, the gap between the 10th century and late 13th century, when the Manx triskelion is first recorded, is wide indeed, and it has been noted that several kings from this period are known to have borne a galley as their emblem, and not a triskelion.
Early examples of the symbol are present in the Royal Arms ascribed to the King of Mann in several late 13th century armorials.
The Manx triskelion also appears on the Manx Sword of State, which is popularly said to date to the time of King Olaf the Black (d. 1237), although recent analysis has shown it more likely dates to about the 15th century.
Another example can be seen on a 14th-century stone cross in the churchyard of Maughold.
Another is example is a late 14th-century seal of Sir William le Scrope, Lord of Mann, in which the Manx triskelion is depicted in plate armour, rather than mail.
Early representations of the Manx triskelion show the legs running clockwise, and later representations show the legs running in both directions. 
Tau Gamma Phi (ΤΓΦ) also known as the Triskelions' Grand Fraternity Triskelion Alumni Organization ( T.A.O. )
— The umbrella organization of all Triskelion alumni worldwide.
Triskelion Order of Law  ( T.O.L. )
— Triskelion Alumni members who are in the judiciary and paralegal profession.
Triskelion Order of Medicine  ( T.O.M. )
— Triskelion Alumni members who are in the medical profession.
Triskelion Order of Business  ( T.O.B. )
— Triskelion Alumni members who are in the corporate world, businessmen and or those who operate their own entrepreneural ventures.
Triskelion Information Technology Organization  ( T.I.T.O. )
— Triskelion Alumni members who are in the Computers and Information Technology profession.
Triskelion Law Enforcers Group  ( TriLEG ) — Triskelion Alumni members who are in the Police, Military and Armed Forces profession.
Bagong Tao Movement   ( B.T.M. )
— A duly accredited political party list organization of the Tau Gamma Phi Fraternity and Tau Gamma Sigma Sorority.
Triskelion Seafarers League   ( TriSEAL ) — Triskelion Alumni members who are working as seamen, navy personnel, and crew in ships that are plying oceans around the globe.
Triskelion Rescue and Emergency Assistance Team   ( T.R.E.A.T. )
— Triskelion Alumni who are members of the Bureau of Fire Protection (BFP), Emergency Medical Services (EMS) and various Fire Volunteer Brigades.
Triskelion Order of Teachers   ( T.O.T. )
- Triskelion Alumni who are in the Teaching Profession.
The group was organized by the initiative of local founders/ lady founders of West Visayas State University Chapter, Iloilo City.