I was under the impression an "activist" judge was one that didn't align with your personal idealogies.
Nope, but you'd be forgiven for having that impression. Liberals are masters of diluting terms they don't like. Don't like the word "terrorism" because you think it unfairly impugns Muslims? Apply the label to all acts of mass violence whether motivated by political ideology or not. Don't like "judicial activism" because it calls out how liberal judges change the strike zone to achieve their desired result? Just redefine it as anything that doesn't align with your personal beliefs. Dilute disagreeable terms until they are meaningless. Once a word means everything, it means nothing.
This dilution is not to be confused with rebranding - another liberal proclivity. "Abortion" becomes "Reproductive Rights/Freedom." "Global Warming" becomes "Climate Change." "Illegal Immigrant" becomes "Undocumented Worker." "Liberal" becomes "Progressive." Etc. etc.