Hello again;) -If it is a work of art *painting with broad strokes* , it means concretely making wide marks with a wide brush. -It could be an idiom as well having an indirect metaphorical sense: Doing any thing in broad strokes means doing it in a general way without giving details. Example: "He didn't say much, he just talked in broad strokes".

If something is described or defined with broad stokes, then only an outline is given, without fine details.