So we keep hearing certain terms and do not really think to know why they came to be. As someone who works with startups, I hear about freelancers all the time.
In the 18th century when kings lost wars, their soldiers were left without any allegiance. Soldiers in the day used to carry lances. These soldiers were free of any allegiance and were hence called Free Lances. They would work for any king who was willing to pay them for their services as mercenaries.
That is the evolution of the term freelancer.
Now you know.