Ðúvý

Ðúvý, or nighttime, is a period of 27 days, or Ïzamúte, during which darkness is above a certain region. This also equals one half of a complete rotation of the planet Ólïvarneð, with the other half being the period of Ïdavý, or daytime. Each year consists of a regular oscillation between Ðúvý and Ïdavý, with each period of daytime or nighttime being marked by one month. Conventionally, the months of Heta (1st), Yota (3rd), Ulta (5th), and Geta (7th) of a certain place are when that region is completely shrouded in darkness, and the rest are when it is in the sunlight.

The terms of Ðúvý and Ïdavý are often used in conjunction with, and thus highly confused with, the term Ýlafe. The former two describe the brightness, and by extension the environmental conditions, that span one Ýlafe, while the latter denotes that exact length of time equivalent to 27 days.