McDonald's new big burger is called the Big Arch. Branding experts say the name makes it sound superior to its rivals.

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• McDonald's has started trials of its new bigger burger — the Big Arch.
• By using a brand name rather than a descriptor, companies can "signal superiority," a marketing professor said.
• The Golden Arches are synonymous with McDonald's, just like Grimace and the Hamburglar.

The prefix "Mc" has become synonymous with the world's biggest burger chain.

It's not just in the name of the company. McDonald's has also launched McNuggets...