[countable] a spacecraft in the shape of a tube that is driven by a stream of gases let out behind it when fuel is burned inside
a space rocket
The rocket was launched in 2007.
The idea took off like a rocket(= it immediately became popular).
2 [countable] a missile (= a weapon that travels through the air) that carries a bomb and is driven by a stream of burning gases
a rocket attack
3 [countable] a firework that goes high into the air and then explodes with coloured lights
4 [uncountable] (British English) (North American English arugula) a plant with long green leaves that have a strong flavour and are eaten raw in salads