The last component of a domain name, such as .com, .edu, .gov, .net, .org, .mil or any of the newer generic top-level domains, or any of the ccTLDs. Abbreviated TLD
A top-level discussion or activity is one that involves the people with the greatest amount of power and authority in an organization or country. a top-level meeting of American generals at the Pentagon. involving the most powerful people in a country, organization etc