This is a link to an article by Nitzan Horowitz on The Den that refers to the slave trade as the "double holocaust" on account of the suffering of those kidnapped and removed from Africa and the suffering of those they left behind.* It it also refers to the Jewish. holocaust as if the holocaust was a purely Jewish affair.
I believe that it's a major error, both politically and academically, to refer to genocides other than the Nazi holocaust as holocausts. Zionists like to make out that the holocaust is unique in terms of sheer numbers, aims and methods. But all histories are unique if only in terms of time and space and many genocides, like the slave trade, outweigh the holocaust for sheer numbers. Calling the holocaust, "the holocaust" does not make it bad. What it consisted of was what made it bad. Similarly the slave trade was bad enough without it being called a holocaust. Those who call it such seem to lack confidence in the description of what actually occurred sufficiently arousing people to condemn it.
Nowadays we are used to hearing the Israelis and Zionist movement compared to the Nazis and the ethnic cleansing of Palestine compared to the holocaust. This doesn't exaggerate Palestinian suffering. Holocaust survivor the late Israel Shahak said that any holocaust survivor would testify that a quick death is better than a slow torture. If that is the case then you could say that Palestinian suffering surpasses the holocaust. But it is not the holocaust. That name belongs to a different episode in history.
Returning to my earlier point, many identity groups, Jews, Irish, Palestinians, native Americans, Africans - the list is literally endless as new genocidal campaigns begin and/or continue - calling their collective and historic suffering holocausts doesn't amplify the suffering, it doesn't (as the Zionists argue) minimise the holocaust; it minimises the suffering by implying that the suffering would not count as suffering en masse if the word holocaust wasn't applied to it.
Perhaps we can agree that the Nazi holocaust was unique, but that that "uniqueness" is shared with the slave trade, the Irish famine, the conquest of the Americas and many many more genocidal campaigns. Not unique by any dictionary definition then.
Finally, the use of the expression "Jewish holocaust" is also an error. It was the Nazi holocaust and killed many more millions than just the Jewish millions.
*Updated 18/1/2005 in the wake of an adverse comment from Dave of the Den.