arms race

1. Continuing competition between two or more countries to achieve superiority in the quantity and destructive capabilities of their military weapons. Though the cease-fire had been signed, tensions remained high in the region, with both countries beginning an arms race to ensure military supremacy. The US and Soviet Union engaged in a nuclear arms race during the Cold War. Other countries will have to take action if the arms race between those two nations continues.

2. By extension, continuing competition between two or more companies, organizations, or groups to achieve supremacy in some industry, market, or area. With the push to create more environmentally friendly transportation, the arms race to develop affordable, competitive electric cars has been heating up recently. The two tech giants have been in a decades' long arms race to control the market for personal computers. Another arms race for social media app supremacy? What else is new?