The most common definition is the use of violence to frighten people into allowing a group to achieve its goals. But there's that cliché about one person's terrorist being another person's freedom fighter: depending on the goals, intimidation by violence sometimes seems like it might be OK.... Thus, Bin Laden blows up a couple thousand innocent people in the World Trade Towers in order to scare the US out of the middle east, and that's bad, and John Brown massacres some slave owners in Kansas to scare other slave owners from coming to the new territories, and maybe that's not so bad... both of them can be called terrorists, but John Brown gets more leniency. In both cases, though, you can say that a small group was trying to coerce a large population through fear of extreme violence.

But that's hard to claim here. Outside of some violence-prone characters like Ethan Allen or Banastre Tarleton, the American Revolution didn't see much terrorism from either side.The Founding Fathers were not representing some small group needing to coerce a majority by extreme violence: it had enough popular support ( perhaps because it was making no extreme demands) to raise and field an army. The British did not lay waste to areas loyal to Washington and massacre the inhabitants, and Washington did not slaughter prisoners or hang Loyalists: indeed, there were prisoner exchanges and paroles, negotiations, and eventually a truce and a peace settlement.