radialis

Forms

radiālis (neuter radiāle); third-declension two-termination adjective^[1]

Etymology

It is formed from Latin radius + -ālis in Medieval Latin, from the noun meaning “ray, spoke, radius”.^[1][2][3]

Earliest recorded meaning

Köbler dates its first record to 1267, from Latham's word-list,^[1] in the sense of radiating or ray-like.^[1]

Semantic evolution

In British sources it describes light that streams out from a source, as in a hymn that calls God a radiant, unending light, and lines that run out from a centre in geometry and optics, as in the treatises on perspective that speak of “radial lines” and a “radial pyramid” of vision.^[3] English radial comes from it.^[2]

Timeline

• 1267 – First record of the word, according to Köbler.^[1]
• c. 1400 – English borrows it as radial, “of or like a ray or radius”.^[2]

Meanings

Adjective

1. (Medieval Latin) Proceeding from a centre, radial.^[3]
2. (Medieval Latin) Of light: radiant, ray-like.^[3][1]
3. (Medieval Latin, geometry) Of a line: running from a centre.^[3]

Related words

• radius
• English radial

References

1. ^ a b c d e f Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
2. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
3. ^ a b c d e Latham, R. E., D. R. Howlett, R. K. Ashdowne, et al. (1975–2013), Dictionary of Medieval Latin from British Sources, London: British Academy / Oxford University Press