I always want to name a variable (or type) accurately after it's actual purpose, so that I don't confuse myself when I read it back later. I would be confused if the variable name lead me to think about irrational numbers.
But I'm not writing the game now. I was just reminded of this by PABLO's post when he mentioned "FRACTIONS".
An irrational number can only be represented by a computer in an abstract form (obviously) so if all youre doing is multiplication, division, addition and subtraction and nothing to do with logarithms, roots, or an operation with pi or e, theres no reason to consider irrational numbers. I understand you want a name that represents any number from 0 to 1, which technically is an infinite set including irrational and infinitesimals, but it appears this name doesent exist. I would call it something like a positive subunitary proportion.
It appears there is a new SI unit to deal with this problem. The unit is called "Uno". Not sure if this is something that is compatible with your issue.
https://archive.iupap.org/commissions/interunion/iu14/ga-99.html
