Definition of 'Megamerger'
The joining of two large corporations, typically involving billions of dollars in value. The megamerger creates one corporation that may maintain control over a large percentage of market share within its industry.
Megamergers occur through the acquisition, merger, consolidation or combination of two existing corporations. Megamergers differ from traditional mergers due to their scale.
Investopedia explains 'Megamerger'
Megamergers in the recent past have included Pfizer's $68 billion deal for Wyeth (2009), Kraft's nearly $20 billion deal for Cadbury (2010) and the United–Continental merger (2010), which created the world's largest airline.
The first megamerger took place in 1901, when Carnegie Steel Corporation combined with its main rivals to form United States Steel.