zero hour
C1-C2Formal, Technical (Military/Journalism)
Definition
Meaning
The exact time when a planned operation or event begins.
A critical or decisive moment; a time of crisis or beginning. Also used in military contexts to denote H-hour, the specific start time of an attack.
Linguistics
Semantic Notes
Often used metaphorically to emphasize the urgency and importance of a starting point. Implies preparation, countdown, and imminent action.
Dialectal Variation
British vs American Usage
Differences
No significant difference in core meaning. Slightly more frequent in UK media/political discourse. In US, 'H-hour' or 'D-day' might be more specific in military jargon.
Connotations
Both carry connotations of urgency, precision, and high stakes.
Frequency
Medium-low frequency in both varieties, found in news, history, and strategic planning contexts.
Vocabulary
Collocations
Grammar
Valency Patterns
Zero hour + for + NOUN (Zero hour for the offensive)At/By + zero hourZero hour + VERB (Zero hour arrived)Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “Zero hour for the economy”
- “It's zero hour for the team.”
Usage
Context Usage
Business
Used for major project launches or critical financial deadlines. 'Tomorrow is zero hour for the product launch.'
Academic
Used in historical or political science texts to denote the start of a significant event. 'The treaty signing was the zero hour for the new alliance.'
Everyday
Rare. Used metaphorically for personal deadlines. '5 PM is zero hour—I must finish this report.'
Technical
Primarily military: the precise time an operation begins. Also in computing/events for scheduled start times.
Examples
By Part of Speech
verb
British English
- The operation was zero-hour-ed for 0600.
- They will zero-hour the initiative at dawn.
American English
- The mission was zero-houred for 0600.
- We need to zero-hour the rollout precisely.
adjective
British English
- The zero-hour contract offered no guaranteed work.
- They made zero-hour preparations.
American English
- He was on a zero-hour employment agreement.
- The zero-hour planning session was intense.
Examples
By CEFR Level
- The meeting is at ten—that's our zero hour.
- Zero hour for the military exercise was set at sunrise, and all units were in position.
- As the climate summit begins, many scientists believe it is zero hour for decisive global action on emissions.
Learning
Memory Aids
Mnemonic
Think of a rocket launch countdown: '3...2...1...Zero!' That 'zero' moment is 'zero hour'—blast off!
Conceptual Metaphor
TIME IS A RESOURCE / A MOMENT OF CRISIS IS A BATTLE.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid literal translation 'нулевой час'. Use 'час икс' (X-hour) or 'решающий момент' (decisive moment). 'Время ноль' is not idiomatic.
Common Mistakes
- Using it for a simple appointment ('My zero hour with the dentist is at 3'). Overusing in informal contexts. Confusing with 'the eleventh hour' (last minute).
Practice
Quiz
In which context is 'zero hour' LEAST likely to be used appropriately?
FAQ
Frequently Asked Questions
No. 'Zero hour' is the start time. 'The eleventh hour' means the last possible moment before something happens, often implying a deadline was almost missed.
Yes, but it's relatively formal and dramatic. It's suitable for major launches, mergers, or critical deadlines to emphasise importance and precision.
It originates from military jargon in the early 20th century, specifically from the practice of timing operations from a designated 'zero' or 'H-hour'.
It's a derived term in UK labour law, meaning a contract with no guaranteed hours. The metaphorical link is the 'zero' point—no work is guaranteed until called upon, much like troops awaiting H-hour.