hiatus

Short definition from Wiktionary

Noun

1. 1
   A gap in a series, making it incomplete.
2. 2
   An interruption, break, pause or absence.
3. 3
   An temporary break from work, especially one which is unexpected.
4. 4
   A gap in geological strata.
5. 5
   An opening in an organ.
6. 6
   A syllable break between two vowels, without an intervening consonant.