diagonal

• adj.斜め; 斜め; あや織り
• n. 斜め; スラッシュ

dia-, 通して。-gon、曲げる、角度をつける、語源的にはkneeの八角形と同じ。

diagonal

diagonal: [16] Diagonal is commonly used simply as a synonym for oblique, but in strict mathematical terms it denotes a line joining two non-adjacent angles of a polygon. This reveals far more clearly its origins. It comes from diagōnālis, a Latin adjective derived from Greek diagónios. This was a compound formed from the prefix dia- ‘across’ and gōníā ‘angle’ (as in English polygon), meaning ‘from angle to angle’. Gōníā is related ultimately to English knee and genuine.
=> genuine, knee, polygon

diagonal (adj.)

1540s (implied in diagonally), from Middle French diagonal, from Latin diagonalis, from diagonus "slanting line," from Greek diagonios "from angle to angle," from dia- "across" (see dia-) + gonia "angle" (see -gon). As a noun, from 1570s.

1. The book has a diagonal black stripe on the cover.

本の表紙には対角を結ぶ黒い斜線がある。

2.Footsteps had scored a diagonal path through the snow.

足跡は雪の上に対角線を残している。

3.Draw a diagonal line to divide the square into two triangles.

対角線を描き、正方形を2つの三角形に分ける。

4.The lumped mass matrix is a diagonal matrix.

集中質量アレイは1つの対用アレイである。

5.The square matrix is called a diagonal matrix.

この正方行列を対角行列と呼ぶ。