Webmaster level: All Change can happen—sometimes, as we saw in our previous post on URL removals , you may completely block or remove a page from your site. Other times you might only change parts of a page, or remove certain pieces of text. Depending on how frequently a page is being crawled, it can take some time before these changes get reflected in our search results.
Excerpt from:
URL removals explained, part II: Removing sensitive text from a page