using System;

public class Program

{

    public static void Main()

    {

        string url = "http://www.merriam-websterwww.com/dictionary/sample";

​

        url = new Uri(url).Host;

​

        if(url.StartsWith("www.", StringComparison.OrdinalIgnoreCase))

            url = url.Replace("www.", string.Empty);

        Console.WriteLine(url);

    }

}