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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 ?
Primary ethmoid SNSCCs make up 5-25% of all sinus malignancies.
Characteristically they arise from lateral nasal wall near the middle turbinate and extend into sinuses usually involving the maxillary and ethmoid sinuses.
Its rostral limit was present at the level of cranial face of first molar tooth and extends upto level of cribriform plate of ethmoid bone (Fig.
The maxillary, ethmoid (divided into anterior and posterior cells) frontal and sphenoid sinuses.
The proportion of mucoceles located in the maxillary and ethmoid sinuses were both 30.
As a result, the ethmoid air cells are rarely limited to the lateral ethmoid masses; they often extend into the turbinates, crista galli and the neighbouring frontal, maxillary, sphenoid and palate bones.
If there was abnormality in ethmoid sinuses then Caldwell view was performed by using an occipitofrontal beam while the nose and forehead were in contact with the film.
Ipsilateral ethmoid sinuses metastasis and proptosis: Rare presentation of metastatic prostate cancer.
Similar to the study population overall, tumors with osteoblastoma-like features occurred most frequently in the frontal (59%) and ethmoid sinuses (44%).
Rennels described as a "poor engineering feature," only a very thin layer of bone--the lamina papyracea, or paper lamina--separates the ethmoid air cells from the posterior orbit.
Sinuses practically surround the orbits, the frontal sinuses above, the ethmoid sinuses medially, and the maxillary sinuses inferiorly.