Astron.
a large prism placed in front of the objective lens or mirror of a telescope, allowing the simultaneous acquisition of the spectra of many stars.
Astron.
a large prism placed in front of the objective lens or mirror of a telescope, allowing the simultaneous acquisition of the spectra of many stars.
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012