A week is a period of seven consecutive days. It can also refer specifically to the five working days from Monday to Friday, as distinct from the weekend.
What Does Week Mean?
Week comes from Old English wice (also spelled wucu), which is related to Old High German wehha and Gothic wiko. The Proto-Germanic root likely carried the sense of "a turn" or "a sequence", reflecting the idea of days cycling in order. The seven-day week itself was adopted in Britain through Roman influence, with each day named after a planet or a Norse deity — Sunday (the Sun), Monday (the Moon), Tuesday (Tiw), Wednesday (Woden), Thursday (Thor), Friday (Frigg), and Saturday (Saturn).
In modern British English, week has two overlapping meanings. In its broadest sense it means any seven-day period: I will be away for a week. More narrowly, it refers to the working or school week, the five days from Monday to Friday: I only see her during the week. The context usually makes the meaning clear.
One distinctively British usage worth noting is fortnight, which means two weeks. This word is common in British English — We are going on holiday for a fortnight — but rare in American English, where two weeks is preferred. British learners are likely to encounter both forms.
Example Sentences
| Sentence | Level & usage note |
|---|---|
| She spends several hours each week practising her listening skills. | A2 — frequency expression with each |
| I have a dentist appointment next week, so I need to leave work early on Thursday. | B1 — planning; next week as time adverbial |
| The report must be submitted by the end of the working week, no later than Friday at five o'clock. | B1 — working week; deadline language |
| After a particularly busy week of back-to-back meetings, she was relieved when the weekend finally arrived. | B2 — collocation busy week; contrast with weekend |
| The project timeline was compressed from six weeks to four, forcing the team to reassess their priorities and redistribute the workload accordingly. | C1 — plural weeks; formal register; complex sentence |
Common Collocations
| Collocation | Example |
|---|---|
| last week | I saw that film last week. |
| next week | The results will be published next week. |
| this week | Are you free any evening this week? |
| every week | He phones his parents every week. |
| once a week | They have a team meeting once a week. |
| working week | A standard working week in the UK is 37–40 hours. |
| busy week | It has been a busy week — I need a rest. |
| a week off | She is taking a week off in August. |
| per week | Students study approximately ten hours per week. |
| week by week | Her confidence improved week by week. |
Usage Notes
Key points for learners
- Possessive forms: use a week's (singular) or two weeks' (plural) before a noun — a week's holiday, two weeks' notice. This apostrophe is required in formal writing.
- During the week means Monday to Friday in British English, implying a contrast with the weekend: I am usually busy during the week.
- Week on week / week by week both describe gradual change over successive weeks, but week on week is more common in business reporting (e.g., sales rose 3% week on week), while week by week sounds more narrative.
- Fortnight (two weeks) is very common in British English and is worth learning as a vocabulary item, even if you choose to use two weeks yourself.
- Week is countable: you can say one week, several weeks, a few weeks. There is no uncountable use.
Common Mistakes
Watch Out For
I haven't seen her since a week. (since requires a point in time, not a duration)
I haven't seen her for a week. (use for with a duration)
She is on holidays the next week. (no article before next/last with time expressions)
She is on holiday next week. (no article; holiday is uncountable in British English)
I will finish it in the end of the week. (wrong preposition + article)
I will finish it by the end of the week. (use by for a deadline)