The term "lucky bone" does not inherently have any synonyms. However, the word "lucky" can be replaced with phrases such as fortunate, serendipitous, or auspicious. Similarly, the word "bone" can be substituted with terms like vestige, artifact, or relic. Thus, alternative phrases like "fortunate relic" or "auspicious artifact" can be used in place of "lucky bone". However, it's important to recognize that these phrases may not convey the same connotation or cultural significance as the original term.