Experimental
I like the word experimental because it fuses two halves of a process we don't usually link. What we typically mean is divergence, deviance, tinkering, norm-breaking. Weird stuff. Think avant-garde John Cage soundscapes where he makes music with only kitchen appliances. But also, the word points directly to the scientific process: to run an experiment means to set boundaries, gather insights, and test a hypothesis. Either mode alone falls short. Endless mutations burn you out, and rigid systems can't take you anywhere interesting.
Many of the original experimental artists were scientific. Kandinsky didn't just make abstract shapes, he developed a systematic theory on how colors/geometry provoked specific feelings, and then at the Bauhaus he used questionnaires to test which of his theories were true. I don't know exactly when this happened, but as weird works became mainstream, the word shifted from a process to a genre; the way it was made mattered less than the fact that it was unusual.
Experimental drifted into a contronym, a single word that contains opposite meanings. The power in the word comes when you re-unite both halves, entering strange territory with an analytical eye.