That would be the vomer.
Vomer bone
Vomer
perpendicular plate of ethmoid bone and inferior is the vomer
Vomer Bone
Vomer, a facial bone, and Ethmoid bone, a cranial bone, form the nasal septum
inferior nasal concha
The vomer is the nasal septum.
The ethmoid bone forms the roof of the nasal cavity. Its perpendicular plate forms part of the nasal septum. Its curved projections form the superior and middle nasal conchae. Its superior projection is called the crista galli.
The primary bone in the septum of the nose is called the vomer bone. The other bone in the nasal septum is called the ethmoid bone.
The ethmoid and the inferior nasal chonchae.
Nasal septum