rocket-n; 3 Senses

Sense Number 1: a self-propelled projectile driven by self-contained propellant

Commentary: ROCKET[+projectile][+self_propelled][+propellant][+self_contained][+missile/+flare/+spaceship/+fireworks] [+role][+conveyance][+transport/+weapon/+signal/+pyrotechnic]

We could only see the vapor trail as the rocket disappeared into the blue sky.
This rocket can be fired at aircraft from a shoulder launch.
The crowd cheered as the rockets rose up and exploded into a display of colorful fireworks.
The Titanic shot rockets into the air as a distress call to other ships.
John and his brother would gladly volunteer to ride a rocket to Mars.
He can throw a fast ball like a rocket. (metaphoric extension, very fast)
Model rockets contain only small amounts of solid rocket fuel. (context suggests 'rocket' refers to the projectile)

WordNet 3.0 Sense Numbers: 1, 4, 5

Sense Number 2: a combustion engine with self-contained propellant

Commentary: ROCKET[+engine][+combustion][+propellant][+self_contained] [+role][+producer][+thrust]
NOTE: similar to a jet engine, but uses own fuel, does not have air intakes like a jet engine
NOTE: refers to the thrust-producing mechanism, not the projectile that flies through the air.

The Saturn rocket engine was designed around the earlier Jupiter and Redstone rockets.
A rocket engine burns liquid or solid fuel.
This is not rocket science. (refers to the technology and craft of the thrust producer)
This engine uses a special type of rocket fuel. (context suggests 'rocket' refers to the engine)

WordNet 3.0 Sense Numbers: 2

Sense Number 3: a plant often grown as a salad crop, arugula

Commentary: ROCKET[+plant][+crop][+salad]

Mary picked lettuce, rocket and scallions from the garden to make a salad.
Garden rocket is best when harvested while young and tender.

WordNet 3.0 Sense Numbers: 3