My interpretation is that you dont want to match "patterns" that occur as part of larger words.
For this look at the use of word boundaries
would suggest a look at perlrequick(perldoc) for such problems,below is what it says about this one.
The word anchor  \b matches a boundary between a word character and a 
+non-word character \w\W or \W\w: 

    $x = "Housecat catenates house and cat";
    $x =~ /\bcat/;  # matches cat in 'catenates'
    $x =~ /cat\b/;  # matches cat in 'housecat'
    $x =~ /\bcat\b/;  # matches 'cat' at end of string

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HTH
chimni

In reply to Re: regex for swear filter by chimni
in thread regex for swear filter by Anonymous Monk

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