The short answer is yes. Most people are familiar with website names like www.yahoo.com or www.amazon.com. The words between "www." and the .com are typically used to identify the business that owns the website or a well-known product or service that is featured on the site. Frequently, this identifier is an abbreviation of the company or product name.
The U.S. Patent and Trademark Office allows these identifiers to be registered as trademarks as long as they are being used in connection with a site that sells goods or services. And the courts offer these domain names the same protection as other types of trademark.