"Old Eli" can have multiple synonyms, depending on the context of its usage. It can be used to refer to a senior citizen, an antique artifact, or a prestigious institution. Some synonyms for "Old Eli" could be "veteran," "aged," "antique," or "historic." If referring to a prestigious institution like Yale University, some synonyms could be "Ivy League school," "elite academic institution," or "prestigious college." Alternatively, if referring to a beloved elderly person, some synonyms could be "respected elder," "senior mentor," "experienced guide," or "beloved grandparent." Ultimately, the synonym used for "Old Eli" would depend on the context and intended meaning.