Definition of Nasmyth–Cassegrain in English:

Nasmyth–Cassegrain

noun

Astronomy
  • An altazimuth reflecting telescope in which light from a Cassegrain secondary mirror is reflected by a tertiary plane mirror through 90 degrees, to be brought to an external focus at the side of the tube at its lower end.

Origin

1970s; earliest use found in Journal of the British Astronomical Association. From Nasmyth + Cassegrain.

Pronunciation

Nasmyth–Cassegrain

/ˌneɪsmɪθˈkasɪˌɡreɪn/