It's also not the suicide rate. It's either the has attempted suicide at least once in their life rate or the thought about it rate. Can't quite remember which, but definitely not the suicide rate.
I'm fairly certain it's attempts now that I've looked at it again. It's been a long time since I've read breakdowns of the studies and what the numbers all mean. It wasn't as simple as 41% of trans people attempt suicide. The numbers went down post transition and I don't think suicide attempts had to be serious attempts to be counted (I think it's worth nitpicking this).
Edit: Tried finding the survey the number comes from and got a bunch of different responses that are just confusing me more at this point. I'm probably done here, since researching suicide statistics isn't a ton of fun.