Define complex Regular Expression

[drbuddha]

Hi,

I want to create a regular expression for the username field on registration, that disallow users from using certain words, and some characters limitations.

By seaching the forums I have found some expressions that could help me, but I'm not sure about the right way to combine it together.

This regex works alone:

(?!^term1$)^.+$

This regex works alone too:

(?!^term2$)^.+$

And this regex, also works alone:

^[a-zA-Z0-9 _-]+$

I want to know how to merge all these three together.
Can someone help me?

Thank you