Joanna Krupa says her defamation lawsuit against Brandi Glanville was way more than hygienic vindication ... she hopes it will inspire others to stand up for themselves in the name of truth.

Joanna arrived at LAX Thursday and was at first slow to talk about her confidential settlement, but then opened up about the meaning behind her legal attack.

As for the saying, "Let bygones be bygones" ... well, it's not hard to read between the lines when it comes to a future friendship with Brandi.