Definition of 'Sucker Rally'
A temporary rise in a specific stock or the market as a whole. A sucker rally occurs with little fundamental information to back the movement in price. This rally may continue just long enough for the "suckers" to get on board, after which the market or specific stock falls.
Also known as a "dead cat bounce" or a "bull trap."
Investopedia explains 'Sucker Rally'
A sucker rally is a buzz word describing a rise in price that does not reflect the true value of the stock. For example, suppose that two high-tech companies, "A" and "B", see an increase in stock price due to reporting strong financial statements, and a separate high-tech, company "C," sees a rise in stock price. If the real reason for the rally turns out to be because of potential acquisitions of A and B, then C will have had a sucker rally, rising along with A and B.