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Phrase(s): batten down the hatches
Fig. to prepare for difficult times. (From a nautical expression meaning, literally, to seal the hatches against the arrival of a storm. The word order is fixed.) • Here comes that contentious Mrs. Jones. Batten down the hatches! • Batten down the hatches, Congress is in session again.
McGrawhill's American Idioms And Phrasal Verbs
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Prepare for trouble, as in Here comes the boss? batten down the batches. This term originated in the navy, where it signified preparing for a storm by fastening down canvas over doorways and hatches (openings) with strips of wood called battens. [Late 1800s]
American Heritage Idioms