The phrase "gone to the wall" refers to something or someone that has experienced a downfall or has failed. There are various synonyms for this phrase, including "gone under," "collapsed," "gone to ruin," "defeated," "down and out," "failed," "bankrupt," "bust," "insolvent," and "ruined." Other similar phrases may include "gone down the drain," "gone up in smoke," "hit rock bottom," and "gone belly up." These synonyms can be used in many different contexts, such as describing a failed business or unsuccessful project, an unsuccessful career, or a person who has lost everything. Overall, these synonyms convey the same meaning and portray the idea of something or someone that has experienced a significant downfall.