According to google the definition of a website is:
A location connected to the Internet that maintains one or more pages on the World Wide Web.
So, in other words as we travel along the cyber-highway the destination is a visual product.
Example: The website and its visual format.
According to google the definition of a web application is:
A web application or web app is any software that runs in a web browser.
So, if a website is the table-cloth then the web applications are the salt, pepper, plates and other features on top. In other words, the parts of a website produces actions or certain functions such as logins, updated spreadsheets, schedules, calculators and such, these web application.
So let’s recap, the website is the visual product and the web application is its functionality or what it can do for you.