The naqus (Arabic: ناقوس, romanized: nāqūs) is a percussion musical instrument, and under that name there are a set of traditions associated with Islamic-Christian relations. It can either be a bell or a wooden plank; in the latter form, it is similar to the semantron.
The Arabic word nāqūs goes back to the Syriac naqosha (from naqash, "to strike") and reached the Aethiosemitic languages with the meaning "gong", "handbell". The show the two meanings of nagus...a billet of wood struck, and a bell or hand-bell.
The instrument called a naqus is also referred to in the Bahá'í document Lawh-i-Naqus, "Tablet of the Bell". This "indicates a pierced wooden clapper-board which had a gong or bell-like function in making a noise when hit with a stick."[1]