The American Heritage Dictionary of Idioms, Second Edition

Senior moment. Think outside the box. Idioms like these can't be understood just from the words that make them up. The American Heritage(R) Dictionary of Idioms explores the meanings of idioms, including phrasal verbs such as kick back, proverbs such as too many cooks spoil the broth, interjections such as tough beans, and figures of speech such as elephant in the room.