Each listed result for a search will show some example text from the beginning of the linked page.  It strips out HTML elements, but if there's any navigational text items, they will stay.

For example, each search result on ikiwiki.info shows "(title) ikiwiki/ (title) Edit RecentChanges History Preferences Discussion" at the start of its results.

A way to name some CSS ids that should be removed in search results within the ikiwiki setup file would work.  Here's something similar that a friend proposed:

http://leaf.dragonflybsd.org/mailarchive/users/2009-11/msg00077.html

(bin attachment on that page is actually a .diff.)