"Putting tail between legs" is a common idiom that refers to someone feeling ashamed or defeated and retreating from a situation. However, there are several synonyms for this phrase that can be used in its place. For instance, one could say "tucking tail," which has the same connotation of feeling defeated and backing down from a challenge. Another option is to use the expression "cowering away," which means to flinch or withdraw from something in fear. Other potential alternatives include "slinking off," "skulking away," or "slinking away," each of which can convey a sense of someone feeling defeated or embarrassed. Using varied synonyms adds depth and interest to your writing and also ensures you don't use the same phrase repeatedly.