While there are several theories, the actual origin of the term remains uncertain.
The three competing theories are:
- Loiner could derive from the name Loidis (in use by the eighth century for the district around modern-day Leeds).
- Another explanation says that in the 19th century there were many yards and closes around Briggate whose back entrances were known as Low Ins or Loins, hence Loiner.
- A third theory is that, in the area of Briggate, locals referred to numerous nearby streets as 'loins' in the local accent, as a corruption of the word 'lanes'. People who gathered in these loins to gossip were therefore termed Loiners.
The mock-classical adjectives Leodensian and Leodiensian are sometimes used by some local sports clubs, and the word Leodensian also features in the lyrics of "I Predict a Riot" by Kaiser Chiefs, although in that context it was referring to John Smeaton, a famous 18th-century resident of the city (who resided in Austhorpe Lodge on the site of Austhorpe Primary School) as a founder of Leeds Grammar School, as a Leeds Grammar School leaver is called an Old Leodensian. The term is commonly used to refer to fans of Leeds Rhinos as well as the club itself, either as The Loiners or Loiners.