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Idiom: a manner of speaking that is natural to native speakers of a language

Every language has its own collection of wise sayings. They offer advice about how to live and also transfer some underlying ideas, principles and values of a given culture / society. These sayings are called "idioms" - or proverbs if they are longer. These combinations of words have (rarely complete sentences) a "figurative meaning" meaning, they basically work with "pictures".
This List of commonly used idioms and sayings (in everyday conversational English), can help to speak English by learning English idiomatic expressions. This is a list, which contains exactly 66 of the most commonly used idioms and their meaning.