Science is so unstable that it is constantly changing their own previous definitions of words, as well as their previously stated CERTAINTIES to dodge all of the ever-developing proofs against their absolute nonsense.
There's nothing impressive about the fact that they now claim theory means something other than what it was once held by all the world to mean. As part of the established scientific process 'at that time', a scientist had a "THEORY" and established a hypothesis based upon said theory and then tested out his hypothesis is one or many ways to find his conclusion. Was his theory correct or incorrect. That's how it worked. Now, because the theory of evolution, among many others, has been so proven wrong for so long, they've completely changed the definition of theory to, once again, move the goal posts, as they are apt to do.
Here is the most common definition of theory from the Webster's New World Dictionary copyright 1968 - this is what the word meant for hundreds of years:
theory - a mere conjecture, or guess.