Un-lacing refers to the act of undoing or loosening a laced item, such as shoes or a corset. Antonyms for un-lacing could include lacing up, fastening, tightening, securing or tying up. These words imply reversing the action of un-lacing and creating a firm, secure connection. Lacing up, for example, suggests tying a knot or bow to keep the laces tight and the item in place. Fastening usually involves the use of a buckle, button, or clasp to hold the item together. Tightening can refer to adjusting a strap or cord to create a snug fit. Overall, the antonyms for un-lacing involve binding, securing, and creating a strong hold on an object.