The belief that money (cash) is more valuable than any other form of investment tool. The "cash is king" phrase is typically used when prices in the securities market are high and investors decide to save their cash for when prices are cheaper.
Warren Buffett has never had so much money to spend.
Cash at his Omaha, Nebraska-based Berkshire Hathaway Inc. (BRK/A) rose past $50 billion at the end of June, the first time it finished a quarter above that level since he became chairman and chief executive officer more than four decades ago.
http://www.bloomberg.com/news/2014-08-04/buffett-waits-on-fat-pitch-as-cash-hoard-tops-50-billion.html