Smileygirl,
DVT stands for Deep Vein Thrombosis, which occurs when a blood clot (thrombus) forms in one or more of the deep veins in your body, usually in your legs. Deep vein thrombosis can cause leg pain or swelling but also can occur with no symptoms. You can read more about DVT here: https://www.mayoclinic.org/diseases-conditions/deep-vein-thrombosis/symptoms-causes/syc-20352557