Search and replace words with code

Thanks a lot srikat, I appreciate the links.

The alinks plugin code is too dense for me to understand and apply on a solution of my own, but the Youtube video send me on the right track.

Here’s what I’ve ended up with (a function that replaces the word “stil” with some divs and paragraphs):

<?php

/*
Plugin Name: Replace word
*/

function replace ($text) {
	$text = str_replace('stil', '<div class="definition_word"><p class="word">stil
</div><div class="definition"><p class="ord">stil:
En benämning på vad du än gillar, och dessutom en apelsin.
</div>', $text);
	return $text;
}

add_filter('the_content', 'replace'); ?>

It gives me a DIV that CSS positions absolute to the right, and it looks like I might get this to work.

Two things that I don’t understand though:

1) The wordlist contains some sixty words with definitions, and although I could, using this method, create one plugin for each definition I’d rather not; in other words, how do I add more than one word for the plugin to search for?

2) What would be the best way of making sure that the plugin only replaces the first occurance of a word on any given page, and not the subsequent ones?

I know that what I’ve come up with isn’t elegant, but I’m more of a brute force type of person, and it can very well be ugly as long as it works.

Any help would be appreciated.