interval interval /ˈɪntɝvəl/

noun

1. () A definite length of time marked off by two instants  ( time interval , interval )
   a definite length of time marked off by two instants
     There will be a 15-minute interval between the two sessions.
   There will be a 15-minute interval between the two sessions.
   
2. () A set containing all points (or all real numbers) between two given endpoints  ( interval )
   a set containing all points (or all real numbers) between two given endpoints
   
3. () The distance between things  ( interval , separation )
   the distance between things
    Fragile items require separation and cushioning
   fragile items require separation and cushioning
   
4. The difference in pitch between two notes  ( interval , musical interval )
   the difference in pitch between two notes