Interpreted as: How do I flush the DNS cache?
When DNS changes have been made to a domain the old DNS record may be cached on your local system or device. In order to clear this cache and get the most up to date DNS records it is sometimes necessary to refresh or clear the DNS cache, this process is known as flushing the DNS cache.
Once the DNS has been flushed, the system will perform a full DNS lookup on the domain the next time it is requested instead of looking in the systems local cache.
For more information, check out the Flush DNS page for up to date information on flushing the DNS on a variety of operating systems including Windows 2000, Windows XP, Windows Vista, Windows 7, Mac OS X and Linux.