Definition of rocketsonde in US English:

rocketsonde

noun

Meteorology
  • A package of meteorological or other scientific instruments which is carried to the upper atmosphere by rocket and there released and allowed to float down by parachute, transmitting automatic radio measurements of the surrounding atmosphere; a sonde carried up by rocket.

Origin

1940s; earliest use found in Science News. From rocket + sonde.

Pronunciation

rocketsonde

/ˈrɒkɪtsɒnd/