Ég vakti fram á nótt.
- I stayed awake until late at night.
The original stem is nátt- (<*naht-), preserved in the genitive plural (although the forms nótta, nóttanna now also exist) and in all stem compounds (e.g. nátthrafn). The -ó- comes from earlier -ǫ́-, created by u-mutation of -á-, a vowel change that is no longer productive.
- (night): dagur
- (night): njóla (poetic)