When I say define I mean your working understanding of what these words or terms mean to you. In other words when you use them this is the meaning you wish to convey. That's my question the rest you do not have to read it just my opinion on the matter, what I would love is your opinion. There is truly no wrong or right opinion, just an inform and a less inform or worse miss inform. So lets share and learn - each one teach one Dictionary definitions are good but they lack the relevance of currency and historical perspective of parlance and or contextual meaning. Too often dictionaries reflect only the dead opinion of the literati and academia. Dictionaries leave out almost entirely like history books the perspective and meanings of the "Underclass". Okay now we have the Urban Dictionary and Wiki but these are not recognized (hence used) in the way classical dictionaries are. Language is a living thing, that reflects the cultural history of the speaker as well as their present position and status in society. Racism: to me is The ability and practice of one group of people to control a significant segment of another group of people through economic, political and social means by imposing laws and promoting and or allowing social customs that is oppressive and restrictive Racialism: to me is the recognition of the existence of difference between peoples and societies - such as phenotypical and cultural. To apply those distinction in such a manner as to function as the defining qualities of a specific class of human beings - called Race/Races Racialism has been taken out of most dictionaries as a separate word and merge with Racism which has caused much confusion today when people discuss Racism Reverse Racism: Is a political tool used to undo Affirmative Action by claiming that giving blacks any form of preferential treatment is a form of Racism. Institutional Racism: The legally and or culturally accepted practices of oppressing or denying peoples their human and or civil rights based on race. Prejudice: is to based your opinion and actions on stereotypes rather than experience Preference: To know and experience and as a result to like or agree as oppose to something else.