Merger, consolidation, amalgamation, and takeover all describe the combining of businesses, but they differ in structure and formality. A merger implies that two roughly equal companies join to form a new entity. Consolidation is slightly more formal and often applies when several smaller units combine into fewer, stronger ones — for example, 'the consolidation of regional offices into three main hubs.' Amalgamation is the most formal term, typically found in legal or official documents. A takeover, by contrast, is not a true merger: one company buys another, and the acquired company often loses its identity. In everyday business news, 'merger' is the most common word, while 'acquisition' (not discussed here) is the neutral term when one company buys another. For example, 'the merger of the two airlines' (equal partners joining) versus 'the takeover of the smaller tech firm by the industry giant' (buyer and target are not equal).
The word 'merger' comes from the Anglo-French legal term 'merger' meaning 'to merge, to sink or be absorbed,' which traces back to the Latin 'mergere' meaning 'to dip, plunge, or sink.' In English, it was first used in legal contexts during the 1700s to describe the absorption of one property right into another. The modern business sense — two companies joining into one — became common in the late 1800s alongside the rise of large corporations.