Adverb
with determination; in a determined manner
Source: WordNetI was a normal child. Which is to say, I was selfish and I was not entirely convinced of the existence of things that were not me, and I was certain, rock-solid unshakably certain, that I was the most important thing in creation. There was nothing that was more important to me than I was. Neil Gaiman
I think a fundamentalist is somebody who believes something unshakably and isn't going to change their mind. Richard Dawkins
he clung to the past determinedly Source: Internet