Real Dictionary

price war
countable noun: If competing companies are involved in a price war, they each try to gain an advantage by lowering their prices as much as possible in order to sell more of their products and damage their competitors financially.

price war in American English
a situation in which competitors selling a certain commodity successively lower prices, as to force one or more out of business
noun: intensive competition, esp. among retailers, in which prices are repeatedly cut in order to undersell competitors or sometimes to force smaller competitors out of business

price war in British English
noun: a period of intense competition among enterprises, esp retail enterprises, in the same market, characterized by repeated price reductions rather than advertising, brand promotion, etc

price war in Retail
noun: A price war is a period of intense competition between enterprises, especially retail enterprises operating in the same market, characterized by repeated price reductions.