keep your powder dry
Preserved but no longer current.
Keep prepared for action; keep your courage up. The phrase comes from a story told of Oliver Cromwell. During his campaign in Ireland he concluded an address to his troops, who were about to cross a river before attacking, with the words — "Put your trust in God; but be sure to keep your powder dry.
Era: ca. 1898 (Victorian)
Sources & notes
Reproduced from Brewer’s Dictionary of Phrase and Fable (1898 edition, public domain; archive.org, retrieved 2026-07-31; OCR text, minor errors possible). Reflects the scholarship and attitudes of its era.
Common questions
What does “keep your powder dry” mean?
Keep prepared for action; keep your courage up. The phrase comes from a story told of Oliver Cromwell. During his campaign in Ireland he concluded an address to his troops, who were about to cross a river before attacking, with the words — "Put your trust in God; but be sure to keep your powder dry.
Is “keep your powder dry” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.