'fly-in' originates from the English words 'fly' and 'in', where 'fly' meant 'to move through the air' and 'in' indicated 'inside or within'.

'fly-in' was coined in the 20th century as aviation became more popular, combining 'fly' and 'in' to describe events where participants arrive by air.

Initially, it meant 'to arrive by flying', but over time it evolved into its current meaning of 'an event where people arrive by aircraft'.