The term 'THE 'TANNEN' OF TANNENBAUM' is a reference to the German-American businessman and philanthropist, Leo Tannenbaum. He was born in Germany in 1883 and immigrated to the United States in 1902. He founded the Tannenbaum Company in New York City in 1910, which became one of the largest wholesale clothing companies in the country. He was also a major philanthropist, donating millions of dollars to various charities and organizations. The crossword solution for this term is FIR, which is an acronym for 'Founded In Respect'. This acronym was chosen to honor Leo Tannenbaum's legacy of respect and generosity.