(edit: Findecanor seems to have posted right before me, so I'm repeating some of what he said)
I would add that I think touch typing also means using 9 or 10 fingers for typing (one thumb can go unused). It also requires that there be some sort of physical indication to aid in finger placement: the homing bars or scoops on F and J.
While you can touch type without such indication, you would then need to either look at the keyboard to get your initial placement, or feel around the keyboard for some other way to locate yourself, which boils back down to physical indication. For example, without homing bars you could still feel around with your hands and count the numbers of keys you touch over to find your initial place, but that's still using physical indication.
I would argue that finding the right spot without physical indication either through luck or a "feel" for the kind of spacing between your hands does not count. Why? Because if I put you on a different shaped keyboard, such as a Kinesis, that feel for spacing would disappear, even though the keys remain in their same relative positions with the exception of the thumb clusters and you could still touch type on one just fine once you found your place.
So what I would say touch typing includes is:
1. Typing without visual assistance.
2. Using 9 or 10 fingers, the excluded one being a thumb if using only 9.
3. Physical indication to aid in positioning in lieu of visual assistance.
You could also make an argument for "proper" fingering while touch typing, which tells which keys should be pressed with each finger. This is similar to there being a "proper" way of playing violin, but then someone came along and invented pizzicato (plucking the violin strings with your fingers instead of the bow) and it can sound pretty good so there's some room for creativity sometimes.
Many of the fastest typists do not follow proper fingering, instead doing what feels natural or what affords them greater speed. That being said, when you take a touch typing class, you will surely be taught proper fingering, so it would be easy to say that that is part of touch typing.