It is a common use -- molding to cover a seam or a gap. It gets used in furniture, in musical instruments, in housebuilding, and everyplace. Is there a name for it? The best I can come up with is "trim molding", which seems too generic. After all, we have these wonderful and specific molding names like astragal, and purfling, and bolection, and such. Why not a name for molding that covers a gap?