Citing a stronger source is not an appeal to authority fallacy.

Since you don’t understand how dictionaries work, here is another source you might understand better:

The Role of Democracy in a Republic

In the United States, the role of democracy within the republic is crucial, embodying the very essence of the electoral process and the engagement of the citizenry in governmental decisions. Although the U.S. Constitution does not embody a pure form of democracy where laws and policies are directly decreed by citizen vote, it enshrines the democratic principle through the election of representatives who, in turn, influence legislation and governance.

If you read the article, you will understand that in order for you to be correct, you need to be using the phrase “direct democracy” or “pure democracy,” which is a specific type of democracy where citizens directly create and vote on laws as referendums. The article agrees that we are NOT a direct democracy, we have a constitutional republic, but we still have a type of democracy because the people have the power to choose their representatives in the republic. Which is the greek and original use of the word democracy.

Hope this helps.