I wish they defined the term fractal... At least whatever they mean by using that word, since fractal has very simple definition and is even measurable (fractal

I wish they defined the term fractal... At least whatever they mean by using that word, since fractal has very simple definition and is even measurable (fractal dimension measure). Fractals tend to repeat their structure at different sizes. Do they mean "unorganized non-abstract shapes with elaborate structure" or something similar?