The answer to the question in the title: “It may be depending on the construction of the cookware.” A Dutch oven is a thick cookware with a lid that fits snugly. It is a multi-purpose cookware that can be used for deep-frying, braising, stewing, making soup and even baking bread. Traditionally made of cast iron, today’s Dutch ovens may be ceramic or enamel-coated metal. They can be used in the oven or the stovetop. Some can be used for cooking directly on fire (such as a campfire).
Despite its name, the Dutch oven has never been exclusively manufactured and used in The Netherlands alone. Cookware fitting that description has been in use in many countries and regions for hundreds of years although they are known by different names. It is called casserole in English-speaking regions except the United States. It is potjie in South Africa, cocotte in France and bedourie in Australia.
The curious thing is that it wasn’t the Dutch who christened their cookware as “Dutch oven”. The Dutch called their cookware braadpan. It was the English that nicknamed it Dutch oven.
The Dutch already had an advanced process of making the cookware as early as the 1600’s. Early in the 1700’s, an Englishman traveled to The Netherlands to study how the cookware was made. He then went back home to England, patented the process and started manufacturing the cookware. He sold it not only in England but to the New World as well. It came to be known as Dutch oven.
So, if a similarly-shaped cookware has thin walls and a loose-fitting lid, it is not a Dutch oven? Correct. It is the thick walls and snug-fitting lid that essentially sets the Dutch oven apart from other cookware that looks like it.
But what’s the big deal about the thick walls and lid anyway? The Dutch oven is so constructed so that food can be cooked in it for a long time with minimal scorching and with very little loss of moisture. When used for deep frying, the thick construction of the cookware helps minimize drops in the temperature of the oil.