They (the ex-imperial pilot) invented the name, while asked for their ship name by some Imperial authority.

rogue

/rəʊɡ/

noun: rogue; plural noun: rogues

  1. a dishonest or unprincipled person.
    • a person whose behaviour one disapproves of but who is nonetheless likeable or attractive.
  2. an elephant or other large wild animal living apart from the herd and having savage or destructive tendencies.
    • a person or thing that behaves in an aberrant or unpredictable way, typically with damaging or dangerous effects.
    • a seedling or plant deviating from the standard variety.

Phrases

go rogue — behave erratically or dangerously, especially by disregarding the rules or the usual way of doing something.

leaders going rogue at press conferences can mean you have a serious problem