If I read your sentence in context... "A type of Italian picture frame with exuberant wood carving evolved during the Baroque period, remained fashionable for a long time, and has never been completely abandoned. Carved wood frames with a “swept” outline, introduced in the 17th century, remained popular in France throughout the reign of Louis XV." ...I think they are describing a picture frame with gentle curves on all four sides. Like this... https://auctions.webbs.co.nz/m/lot-details/index/catalog/205/lot/32792/A-Pair-of-French-17th-Century-Portraits So instead of having very basic rectangular picture frames with straight edges, the Italians and French began to make picture frames with curving "swept" shapes and decorative carving. When you "swipe" the floor with a broom, you make a gentle curve in the dust. It's not a straight line, and it's not a perfect arc or circle, it's just a gentle curve. That is the shape they are trying to describe when they say "Carved wood frames with a “swept” outline.".

I believe it's another term for an extremely smooth curve on a smooth, outer-beveled edge. https://www.morphets.co.uk/68203/A-set-of-seven-walnut-single-chairs-by-A-E-McLintock-of-Market-Hill-Barnsley-each-having-a-broad-top-rail-of-swept-outline-moulded-and-carved-with-acanthus-above-fruit-in-relief-to-the-centre-ab?Itemid=&ipp=10&view=lot_detail I think a visual example might help you better. The description of the chair has it. www.italki.com/garyalexander

Hey. In this case it would circular-like patterns around the frames. Imagine you were to "sweep" across a huge page/canvas or in this case, a huge piece of wood with your hand (and arm). You'd get a somewhat curved/circular pattern because of how your arm moves, yes? That's how it means. I'll try share some images which *might* help. Not about tthe object itself, but the pattern/design for these items. https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.123rf.com%2Fphoto_110172491_stock-vector-outline-delicious-candy-sweet-snack-texture-vector-illustration.html&psig=AOvVaw2y4k_pKbrfLMt8_ErIJjHq&ust=1597503785016000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCJDzsuf7musCFQAAAAAdAAAAABAD https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.stonecontact.com%2Fproducts-507038%2Fpink-marble-residence-pillar-design-natural-stone-marble-column-for-sale&psig=AOvVaw1DqQvgM8mvA2lvmkjQ6F9n&ust=1597504082595000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCOjr4s38musCFQAAAAAdAAAAABAU Sweeps are usually considered to be big (strokes), instead of small circular patterns -- going over the object. In this case, Hope this helps!