Nasal index - bishisuu (English spelling) nasal index

A term in anthropometry, the ratio of nasal width to nasal height multiplied by 100. When viewed from the front, the human nose can be likened to an isosceles triangle, and the nasal index corresponds to the ratio of the height and base of this triangle. In living organisms, nasal height refers to the distance between the root of the nose (the intersection of the frontonasal suture and the midline) and the subnasal point (the apex of the angle between the nasal septum and the skin surface of the upper lip) (commonly known as nasal height, in anthropometric terms, it is called nasal depth), and nasal width refers to the maximum width of the left and right nostrils. The nasal height and width of the skull are determined separately in relation to those of living organisms. In living organisms, an index of 70.0 to 84.9 (47.0 to 50.9 on the skull) is called a medium nose, and a smaller index is called a narrow nose, and a larger index is called a wide nose. Roughly speaking, narrow noses are common in Caucasians, medium noses are common in Mongoloids, and wide noses are common in Negroids and Australoids. Additionally, women have a slightly smaller nose index than men.

[Shise Kahara]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

人体計測学における用語で、鼻高に対する鼻幅の比を100倍したもの。人間の鼻は前方から見ると、二等辺三角形になぞらえることができるが、鼻示数は、この三角形の高さと底辺の比に相当する。生体において鼻高とは、鼻根点（前頭鼻骨縫合と正中線との交点）と鼻下点（鼻中隔と上唇皮膚表面とがなす角の頂点）との間の距離をさし（俗にいう鼻の高さは、人体計測学用語では鼻深という）、鼻幅は左右の鼻翼の最大幅をいう。頭骨の鼻高・鼻幅は生体のそれと関連して別途に定められている。生体の場合、示数70.0～84.9（頭骨では47.0～50.9）を中鼻といい、これより小なるものを狭鼻、大なるものを広鼻という。大ざっぱにいって、狭鼻はコーカソイド、中鼻はモンゴロイド、広鼻はネグロイドおよびオーストラロイドに多い。また女性のほうが男性に比べ、鼻示数は若干小さい。

［香原志勢］

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