| 释义 |
sphenoid, a. and n.|ˈsfiːnɔɪd|
Also 8 sphænoid, 9 sphenoïd.
[ad. mod.L. sphēnoidēs, sphēnoeidēs († sphæno-), a. Gr. σϕηνοειδής, f. σϕήν wedge: see -oid. So F. sphénoïde (1611).]
A. adj. sphenoid bone, a bone of irregular form situated at the base of the skull, where it is wedged in between the other bones of the cranium.
1732Monro Anat. (ed. 2) 76, I have seen separate..Bones at the Conjunction..of the sphenoid and parietal Bones. 1766Phil. Trans. LVII. 119 Portions of medullary substance lying upon the sphænoid bone. 1831R. Knox Cloquet's Anat. 41 The sphenoid bone is articulated with the frontal, ethmoid, occipital, parietal, and temporal bones. 1884M. Mackenzie Dis. Throat & Nose II. 232 The posterior third of the roof..is formed by the body of the sphenoid bone.
B. n.
1. Anat. The sphenoid bone; one or other of the separate parts of this.
1828Stark Elem. Nat. Hist. I. 28 In the fœtus the occiput is divided into four parts, the body of the sphenoid into two. 1841T. R. Jones Anim. Kingd. 638 These two halves may..be called, respectively, the anterior and posterior sphenoids. 1896tr. Boas' Text Bk. Zool. 362 In the basal and lateral regions in front of the parts just mentioned are the sphenoids (ali-, orbito-, and basi-shenoid).
2. Cryst. A wedge-shaped crystal bounded by four equal and similar triangular faces.
1855Orr's Circ. Sci., Inorg. Nature 435 The Rhombic Sphenoid, or, Irregular Tetrahedron, is a hemihedral form, derived from the double four-faced rhombic pyramid. Ibid., A sphenoid may be derived from every one of the pyramids previously described. 1878Gurney Crystallogr. 78 A closed figure bounded by four similar isosceles triangles..is sometimes called a sphenoid. |