The Nagal staff was a sceptre carried by the Grand Nagus of the Ferengi Alliance as a symbol of his authority and power. The figurehead was that of a Ferengi man.
Grand Nagus Zek had to use the staff as a cane due to his advanced years. When Zek retired in 2375 and named Rom as his successor, Zek also passed the staff to Rom. (DS9 episodes: "The Nagus", "The Dogs of War")