Share this entry

facula Line breaks: fac¦ula
Pronunciation: /ˈfakjʊlə/

Definition of facula in English:

noun (plural faculae ˈfakjʊliː)

1A bright region on the surface of the sun, linked to the subsequent appearance of sunspots in the same area.
Example sentences
  • Associated with sunspots are brighter areas called faculae.
  • If the faculae loom above the surface, they could radiate light efficiently, thereby boosting the sun's overall brightness, especially during the solar maximum.
  • Although not easily discerned in telescopic views of the Sun, these features are brilliant enough that the overall effect of the combined spots and faculae is to boost irradiance levels.
1.1A bright spot on the surface of a planet.


Early 18th century: from Latin, diminutive of fax, fac- 'torch'.



Example sentences
  • During sunspot maximum, both increased facular activity and increases in the magnetic network of bright regions associated with supergranulation are required to explain the increased luminosity.
  • The competing effects of bright "facular" regions and dark sunspots, both of which are more numerous at solar maximum, seem to explain this variation.

Words that rhyme with facula

Dracula, oracular, spectacular, vernacular

Definition of facula in:

Share this entry


What do you find interesting about this word or phrase?

Comments that don't adhere to our Community Guidelines may be moderated or removed.

Get more from Oxford Dictionaries

Subscribe to remove adverts and access premium resources

Word of the day innocuous
Pronunciation: ɪˈnɒkjʊəs
not harmful or offensive