Well, I knew what Zed meant. But in many bathrooms, er, washrooms, here, there is bar (or some other, usually decorative, shape) soap that actually IS in a dish--except for the folks who just let it reside on the edge of the sink--and we DON'T call that dish soap! I've gotten to where I say dishwashing liquid, as a way to keep the meaning separate from dishwasher detergent. From what I understand, woe betide the poor schmuck who puts dishwashing liquid in their automatic dishwasher. (Man, I hate my use of the word their, there! But couldn't bring myself to put 'his'.)