It doesn't always take an outside force to make something suppressed — you can do it yourself. You might occasionally have a suppressed feeling of rage. (Psychiatrists, who are in the business of bringing such feelings to light, might frown on this.) Sometimes something that's suppressed is also oppressed — that is, harshly put down or brutally controlled, like a suppressed minority group. Both suppressed and oppressed come from the same Latin word, opprimere, meaning "to press against, or crush."