Japanese people are given surnames for a variety of reasons, including place names, ancestral experiences, and as a symbol of good luck. The surname "tachibana" in this song is a symbol of prosperity for descendants because tachibana is an evergreen tree and its leaves grow thick even in winter. Furthermore, when pronounced in Japanese, the surname contains the sound "tathi," which means "sword," and because of these two meanings, it was chosen as the surname of a samurai family and has been passed down to the present.