The phrase "out of the window" (or "out the window") has two primary meanings.
Literally, it means passing through or looking outside via a physical window.
Idiomatically, it means that a plan, idea, or principle has completely disappeared, failed, or been discarded.
In conversation, this idiom describes a situation where plans, logic, or principles are ruined or abandoned. It gives the mental image of tossing something away so it is completely gone.
Physically, the phrase describes movement away from, or a line of sight directed through, a window.
Examples:
"She looked out of the window to check the weather."
"The cat jumped out of the window."
To explore more figurative language and see how these phrases are used in different contexts, you can browse idioms and phrases on Cambridge Dictionary or Wiktionary.
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