British historians tend to refer to the conflict as the American War for Independence (or some variation thereof). Many American scholars recognize that it wasn’t very ‘revolutionary’ in modern terms, but the name has stuck.
The original meaning of the term revolution was a return to something. For example, RPM (revolutions per minute—something circular). When the English threw out James II and put William & Mary on the throne in 1688, it became known as the Glorious Revolution. While there is a lot of politics involved in this, what was essentially implied by the term ‘Glorious Revolution’ was that order had been restored to the monarchy and the country.
Similarly, the American Revolution was restoring the situation in America to the way it had been before the 1760s and 70s, during Salutary Neglect. The works of Jack P. Greene explain this issue best, but I’ll try to summarize: Throughout the period of Salutary Neglect, the various colonial legislatures in America acquired the rights to govern their own internal matters: internal taxation, domestic laws, payment of the governors salary, payment of judges salary, etc. Parliament always maintained the right to make decisions concerning foreign policy matters: war, Indian relations, import and export tariffs, etc. This is all part of the invisible imperial constitution, based on precedent, that was understood as the law of the empire (keep in mind Britain did not, and does not, have a written constitution). Essentially, the hallmark of Salutary Neglect was weak central government and strong local (colonial) governments.
Well Salutary Neglect comes to an end after the Seven Years’ War in 1763. Parliament begins trying to tighten its control over the colonies via the Proclamation Line of 1763, Sugar Act of 1764, Quartering Act of 1765, the Stamp Act of 1765, etc. All of these acts were seen by many Americans as changing the nature of the relationship between mother country and colony—as trying to subvert the established invisible imperial constitution. So, eventually, the Americans rebelled, they won, and they established a new form of government. (That was easy, right?)
The Americans initially formed the kind of government that would restore the situation in America that they had experienced during Salutary Neglect: a weak central government and strong local (state) governments. This was the Articles of Confederation government. The American Revolution was a conservative, or preservative revolution, trying to restore the status quo from the period of Salutary Neglect. Thus it got termed a revolution because it was an attempt to ‘restore’ or ‘return’ to something—much like the Glorious Revolution of 1688 before it.
Our modern understanding of the word revolution is based more on the French, Haitian, and Russian revolutions—where the order of society was completely flipped (bottom class on top post-revolution). That certainly didn’t happen in the American Revolution. The same sort of rich white guys who ruled over colonial societies, ruled over American society after the Revolution.
Ultimately, they realized the Articles of Confederation wasn’t going to work, drafted the Constitution, ratified it (despite the vigorous protest of many, worried about a powerful central government) and the structure of government we have today was more or less born. This form of government, the Constitution, was new and unique and I’d venture a guess that it had something to do with changing the perception of the term revolution, but that is mere speculation on my part.
There’s a whole lot more to this story, but hopefully that helps.