Definition of rastrum in US English:

rastrum

noun

Music
  • A multi-nibbed pen designed for drawing all the lines of a musical stave simultaneously.

Origin

Late 19th century; earliest use found in John Stainer (1840–1901), musicologist and composer. From classical Latin rāstrum rake from rādere to scrape + -trum, instrumental suffix. Compare German Rastral.

Pronunciation

rastrum

/ˈrastrəm/