To a certain extent it is accurate to call the American Revolution a civil war. The colonists were under British control at the time, between regions of the same country. It becomes a war between two nation states. Within the colonies, Revolutionaries were not only fighting against the British but also with the Loyalists who still believed and agreed with the king. As Britain being the overall state, it was a war within their sovereign, but also within their country. But, the American Revolution was the colonists believing that they had a right to develop their own country and succeed from Britain. During the battle of Kings mountain one side consisted of Loyalists under British control and serving in their army.
The other side consisted of Patriots who were the overmountain men. Both sides were completely American but one side supported Britain and the other opposed. The American Revolution was to overthrow the government and start to create one of their own, which is exactly what is what it was. So although the American Revolutionary War was between those of the same citizens, like a civil war, it also falls under the definition of a Revolution.
Although some do believe that the Revolutionary War was, just that. But taking into consideration the fact of the colonies being an actual part of Britain and being a war within Britains control and their provence, it can be considered a Civil war. So to a certain extent, the Revolutionary War can be considered a Civil War.