regex - Need to find a regular expression for any word except word1 or word2

Question

Basically I need a regex which will return true if the string is a word (w+) EXCEPT if it is the word word1 OR word2.

I've tried many things but dont think I'm even close. Help!

Answer 1

^(?!(?:word1|word2)$)w+$

should do what you need.

(?!...) is a negative lookahead assertion that ensures that it is not possible to match the enclosed expression at the current position.