There are actually seven meanings listed in OED's entry to the phrase greatest, among and that is labelled obsolete. See ‘That means & use’ for definitions, use, and quotation proof. It had been the longest solitary—in runtime—to get to the leading British charts at that time, and in 2013, Billboard https://greatestmusicever42851.amoblog.com/facts-about-what-is-the-greatest-song-ever-written-revealed-57751511