A few weeks ago I talked about the slang “drink the Kool-aid.” Here is another contemporary slang expression that you won’t find in the dictionary.

To “throw someone under the bus” means to blame them for something they are not responsible for. As with “drink the Kool-aid,” it is often used when talking about sports or politics.

After they lost the championship game, the coach threw his star player under the bus. (The coach didn’t take responsibility; he blamed his player.)

When the presidential candidate was accused of bribery, he threw his campaign manager under the bus. (The candidate blamed his campaign manager for the problem).

This site lists other word and phrases that are new to English and, thus, probably not yet in your dictionary.