From a pure linguistics perspective, the answer is "percent".
In mathematics, a percentage is a number or ratio expressed as a fraction of 100.
0.12 and 12% are as equivalent, as 0.1234 and 12.34% are. If the numbers you are expressing are proportional then percent is as valid as anything else.
However, you question wasn't about linguistics, it was about naming variables in which case percent/ration/unit are all terrible variable names. When naming variables, succinctness is of far less importance than readability. Variable names can be minimised or optimised by the complier, as a programmer your role is writing human readable code first, and machine readable code second.
As a programmer, the variable name should have some better context than a unitless proportion, so re-evaluate what you are storing, determine what the actual value means, and try again (probably on Programmers.SE).