the univalent group, C 2 H 5 –, derived from ethane.
- Ethmoidal labyrinth
ethmoidal labyrinth n. A mass of air cells with thin bony walls forming part of the lateral wall of the nasal cavity. Also called ectethmoid.
- Ethmoidal foramen
ethmoidal foramen n. Either of two foramina, anterior and posterior, formed by grooves on either edge of the ethmoidal notch of the frontal bone and by similar grooves on the ethmoid bone.
- Ethmoidal crest
ethmoidal crest n.
- Ethmoidal cell
ethmoidal cell n. Any of the cavities in the ethmoid bone that are filled with air and that communicate with the nasal cavity.