sphenoidal sinus n.
Either of a pair of cavities in the body of the sphenoid bone that communicate with the nasal cavity.
- Sphenoidal spine
sphenoidal spine n. A rearward and downward projection from either of the greater wings of the sphenoid bone. Also called alar spine, spinous process.
- Sphenoid bone
noun 1. the large butterfly-shaped compound bone at the base of the skull, containing a protective depression for the pituitary gland sphenoid bone n. A compound bone with winglike processes, situated at the base of the skull.
- Sphenoid crest
sphenoid crest n. A vertical ridge in the midline of the anterior surface of the sphenoid bone.
sphenoiditis sphe·noid·i·tis (sfē’noi-dī’tĭs) n. Inflammation of the sphenoidal sinus. Necrosis of the sphenoid bone.