what does auxiliary boiler mean?

AUXILIARY BOILER as NOUN

Meaning
- (nautical) an extra boiler (as a ship’’s boiler that is used while the ship is in port)
Synonym(s)
- donkey boiler (what does donkey boiler mean?)
Hypernyms(s) auxiliary boiler is a kind of… Example: animal is a hypernym of mammal, plant is a hypernym of flower
- boiler (what does boiler mean?)
- steam boiler (what does steam boiler mean?)