What does "KHTML, like Gecko" mean in a user-agent string?

I understand that KHTML is the HTML Layout Engine used, but what significance does the "like Gecko" part have? Why is it there?

Is there a historical reason similar to the "Mozilla" part of the User Agent String?

Konqueror began to pretend to be "like Gecko" to get the good pages, and called itself Mozilla/5.0 (compatible; Konqueror/3.2; FreeBSD) (KHTML, like Gecko).

For more information, read:

• Andersen, Aaron (September 3, 2008) - History of the browser user-agent string - WebAIM