Permalinks and url

just wanted some help. When i was creating my pages, wordpress created permalinks for the page names that weere created.
eg. page name “career videos”
so the url is http://www.abcde.com/career-videos.

now i had to change the page name of ‘career videos’ to ‘career media’.
however, the url(http://www.abcde.com/career-videos) doesn’t change to reflect career media (http://www.abcde.com/career-meida). it still shows the contents of the page which is fine.

wondering if there is a cache something somewhere to clear?