Yep, that's it.

The NFL in the US has famously gone to great lengths to downplay the impact of CTE on current and retired players. And there have been several famous players who literally lost their minds as they aged, and we now know that was due to CTE. Something like 90% of ex-NFLers have it. The number is still really bad for collegiate players. And even high school players are at risk.

It was to the point that Will Smith starred in a movie about it. https://en.wikipedia.org/wiki/Concussion_(2015_film)

Yeah - Muhammad Ali is the most famous victim (or at least likely victim, I don’t think he was officially diagnosed with CTE as it wasn’t well understood back then). In the UK, it’s gradually becoming recognised as a serious problem in rugby.

I assumed the C stood for Concussion. Wrong but also partly right!