Depends on your definition of "appropriate and -- if you're writing this for a third party, what the third party considers "appropriate."
Matches such as you listed don't give me any heartburn... except, that is, the annoyance which grows out of getting [some|many|mostly} irrelevant responses to straightforward search terms.
And there are obvious approximate matches that may annoy some of your hypothetical users. But stop without reading more if scatological phrases bother you.
Consider: should your user type "fort" would "fart" be an appropriate response? How about close matches for "shut?"
And what if your user-entered word matches something offensive in another language? These are just a few of the issues you need to resolve.
<code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>