It is a figurative term first used by traders in the financial industry in the mid-1980s to describe a pattern where a stock price plummets and then is followed by a moderate and temporary rise before resuming its free fall. It is derived from the notion that even a dead cat will bounce if it falls from a great height.More here.
Then there is another divine turn of phrase, dog whistle politics.
Dog whistles are built in such a way that humans cannot hear them due to their high frequency, but dogs can. Similarly, dog-whistle politics uses coded language that appears to mean one thing to most people but has a more specific meaning for targeted subgroups, in McCain's case racists and Evangelicals, among others.More here.
Editors note: The cat in the photograph is not dead.