Regex - Matching Abbreviations of a Word

[parRambSarm]

I was thinking in providing the following regex as an answer to this question, but I can't seem to write the regular expression I was looking for:\[code\]w?o?r?d?p?r?e?s?s?\[/code\]This should match a ordered abbreviation of the word \[code\]wordpress\[/code\], but it can also match nothing at all.How can I modify the above regex in order for it to match at least 4 chars in order? Like:

• word
• wrdp
• press
• wordp
• wpress
• wordpress

I'd like to know what is the best way to do this... =)