Weak vs. Week
“Weak” and “week” are homophones in standard pronunciation but have unrelated meanings and parts of speech.
Use “weak” as an adjective meaning not strong, powerful, convincing, or effective. Use “week” as a noun for a seven-day period or related workweek sense.
Key details
Choose the right form
| Meaning / context | Use | Decision |
|---|---|---|
| lacking strength, force, quality, or effectiveness | weak | Use the adjective. |
| a period of seven days | week | Use the time noun. |
| you can replace it with “seven days” | week | That substitution points to the time word. |
Quick tests
Decision test
Does the sentence refer to a period of seven days?
If yes: Use “week.”
If no: If it describes lack of strength or effectiveness, use “weak.”
Caveat: Use ordinary, non-medical examples for the adjective unless a medical claim is independently supported.
Examples
The signal is too weak to reach the basement.
“Weak” describes insufficient strength.
The office will close for a week.
“Week” is the seven-day time noun.
Sales were weak last week.
The sentence uses both homophones with different roles.
Further guidance
Core difference
Use the adjective.
Fast Test
Use “week.” If it describes lack of strength or effectiveness, use “weak.”
Usage Boundary
Use ordinary, non-medical examples for the adjective unless a medical claim is independently supported.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- WEAK | English meaning — Cambridge Dictionary (opens in a new tab)Cambridge University Press · Direct Cambridge dictionary evidence contrasting weak at/in a subject with strong in another subject.
- week (opens in a new tab)Cambridge University Press · Week is a noun for a seven-day period (and related workweek senses) and is pronounced /wiːk/.