When HMS Dreadnought was commissioned in 1906, it was so much larger,
faster, and more powerful than any other existing battleship that it
rendered all others ineffective. Consequently, the name was imposed as a
nickname to other vehicles (within the British Empire) that appeared to
have a similar effect on older models. Thus, when the first bogie electric
trams appeared in Melbourne (P&MTT 1912, later "O" class) they naturally
became popularly known as "Dreadnoughts" - it is easy to imagine how they
dwarfed the single-truck trams, and towered over contemporary cable trams.
In Brisbane, the bogie Centre-Aisle tramcars predated that battleship by a
number of years, however the name was later applied and became common usage.

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