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1. sievelike; cribriform.

eth·moid bone

an irregularly shaped bone lying between the orbital plates of the frontal bone and anterior to the sphenoid bone of the cranium; it consists of two lateral ethmoidal labyrinths of thin plates enclosing air cells, attached above to a perforated horizontal lamina, the cribriform plate, from which descends a median, vertical, perpendicular plate in the interval between the two labyrinths; the bone articulates with the sphenoid, frontal, maxillary, lacrimal, and palatine bones, the inferior nasal concha, and the vomer; it enters into the formation of the anterior cranial fossa, the orbits, and the nasal cavity, forming the supreme, superior, and middle conchae of the latter.


/eth·moid/ (eth´moid)
1. sievelike; cribriform.
2. the ethmoid bone; see Table of Bones. .ethmoi´dal


(ĕth′moid′) also


Of, relating to, or being a light spongy bone located between the ocular orbits, forming part of the walls and septum of the superior nasal cavity, and containing numerous perforations for the passage of the fibers of the olfactory nerves.
The ethmoid bone.


Etymology: Gk, ethmos, sieve, eidos, form
1 pertaining to the ethmoid bone.
2 having a large number of sievelike openings.


(eth'moyd) [TA]
1. Resembling a sieve.
2. Relating to the ethmoid bone.
Synonym(s): ethmoidal.
[G. ēthmos, sieve, + eidos, resemblance]

ethmoid (ethˑ·moid),

n the very thin bone structure of the nose, through which the ethmoid sinuses and other neural structures pass.
Enlarge picture


1. sievelike; cribriform.
2. the ethmoid bone.

ethmoid bone
the sievelike bone that forms a roof for the nasal fossae and part of the floor of the rostral cranial fossa. See also Table 10.
ethmoid sinus
see concha.
References in periodicals archive ?
Surgeons used a headlight, grasping or biting forceps, and ethmoid curettes.
35) Frontal cephaloceles may present through a defect in the anterior cranial fossa into the ethmoid sinus or nasal cavity.
Sphenoethmoidal/Onodi cells represent contiguous extension of the posterior ethmoid air cells laterally and superiorly to the sphenoid sinus, and are closely associated with the optic nerve.
The most common locations are frontal, ethmoid, maxillary, and sphenoid sinuses in that order.
Frontal truncate anteriorly, not extending forward over nasal cavity, thereby partially exposing ethmoid.
The frontal sinus originates from the frontal recess, which is the most anterior part of the anterior ethmoid cells, and grows into the frontal bone.
There are two hypotheses for this recurrence in the left ethmoid and frontal sinuses.
The bulla ethmoidalis is a prominent anterior ethmoid air cell (Fig.
The adjacent paranasal sinuses were frequently involved, especially the ethmoid sinus.
At the time of surgery a well-defined ethmoid bulla was encountered in the left middle meatus (figure, B).
1,5,6] We describe here a case of primary TCRBCL of the ethmoid sinus in a 51-year-old man who had an excellent response to combined chemotherapy and radiotherapy.
The objectives of the study are to evaluate the safety and effectiveness of Entellus Medical's FinESS system in treating subjects with CRS in the maxillary or maxillary plus anterior ethmoid sinuses.