spiral

• n. スパイラル; 渦; 螺旋状のもの
• adj.らせん状；旋回する
• vt. らせん状にする；らせん状に巻き上げる
• vi.らせん状にする；らせん状にする；らせん状に巻き上げる（過去形 spiraled/spiralled、過去分詞 spiraled/spiralled、現在分詞 spiraling/spiralling、三人称単数 spirals、副詞 spirally)

ラテン語のspipralisから、回転、螺旋、spiraから、コイル、巻き、PIE*sperから、回す、回転する、おそらくPIE*spenから、曲げる、回す、織る、語源的にはスパイダー、スピンと同じ。

spiral

spiral: [16] Spiral comes via French spiral from medieval Latin spīrālis ‘coiled’, a derivative of Latin spīra. This in turn went back to Greek speira ‘coil’. English also acquired the noun, as spire [16], which is used for the ‘tip of a spiral shell’. It is not the same word as the spire of a church [OE], which originally meant ‘stalk, stem’, and may go back ultimately to the base *spī- (source of English spike ‘pointed flower head’ and spine). The spiraea [17] is etymologically the ‘coiled’ plant; and spiraea in turn was used to form the term aspirin.
=> aspirin, spiraea

spiral (adj.)

1550s, from Middle French spiral (16c.), from Medieval Latin spiralis "winding around a fixed center, coiling" (mid-13c.), from Latin spira "a coil, fold, twist, spiral," from Greek speira "a winding, a coil, twist, wreath, anything wound or coiled," from PIE *sper-ya-, from base *sper- (2) "to turn, twist." Related: Spirally. Spiral galaxy first attested 1913.

spiral (v.)

1726 (implied in spiraled), transitive, from spiral (n.). Intransitive use by 1834. Transferred and figurative sense by 1922. Related: Spiraling.

spiral (n.)

1650s, from spiral (adj.). U.S. football sense is from 1896. Figurative sense of "progressive movement in one direction" is by 1897. Of books, spiral-bound (adj.) is from 1937.

1. The process is not a circle but rather a spiral .

このプロセスは円周運動ではなく螺旋上昇型である。

2.The spiral of terrorism becomes never-ending.

テロ活動はきりがなく、エスカレートしている。

3.The birds circled in a slow spiral above the house.

鳥が家の上空をゆっくり旋回している。

4.Her hair was styled into a cascade of spiral curls.

彼女の髪は滝のような螺旋状のカルボニル髪になっている。

5.Their profits began to spiral down disastrously.

彼らの利益はらせん状に急激に低下し始めた。