"Left high and dry" is a phrase used to refer to a situation where someone is left without any help, support, or resources that they need to get something done, achieve their goals or succeed. This phrase is often used in informal or colloquial situations. The antonyms, or opposites of "left high and dry" could be "supported, helped, assisted, aided, or backed up." These words imply that someone is providing assistance, resources, or support to someone who needs it, helping them to achieve their goals or succeed, rather than leaving them completely alone and stranded. These antonyms are the opposite of feeling abandoned, insecure, or helpless.