ギリシャ語のparallelos, side by side, parallel, para-, beside, around, -allel, alter, another, 語源的にはelseと同じ, alternate.
英語の語源
parallel
parallel: [16] Etymologically, parallel simply means ‘beside each other’. It comes via French parallèle and Latin parallēlus from Greek parállēlos. This was a compound formed from pará ‘beside’ and allélōn ‘each other’, a derivative of állos ‘other’ (to which English else is distantly related). => else
parallel (adj.)
1540s, from Middle French parallèle (16c.) and directly from Latin parallelus, from Greek parallelos "parallel," from para allelois "beside one another," from para- "beside" (see para- (1)) + allelois "each other," from allos "other" (see alias (adv.)). As a noun from 1550s. Parallel bars as gymnastics apparatus are recorded from 1868.
parallel (v.)
1590s, from parallel (n.).
例文
1. Parallel lines will never meet no matter how far extended.
どんなに長く伸びても、平行線は決して交差しない。
2.Farthing Lane 's just above the High Street and parallel with it.
法辛巷はちょうど通りの北にあり、通りと平行している。
3.Do the emotions develop in parallel with the intellect？
感情と知能は並行して発展しているのだろうか。
4.This a real world，running parallel to our own.
これは真実の世界であり、私たちの世界と共存しています。
5.It 's an ecological disaster with no parallel anywhere else in the world.