# thou

/ˈðaʊ/ (US)

Source: https://englishreference.com/word/thou
Updated: 2026-06-19

## Senses

### 2. one thousand

noun · CEFR C1 · Informal · Slang

a short way of saying 'a thousand', usually referring to money.

For teachers: a colloquial clipping of 'thousand', frequently applied to currency units.

- The repairs on the car are going to cost at least a couple of thou.
- He managed to clear ten thou in a single weekend of trading, though he lost half of it by Monday morning.

### 3. one thousandth of an inch

noun · CEFR C2 · Technical

a very small unit of length used by engineers.

For teachers: a unit of measurement equal to 0.001 inches, commonly used in precision engineering and manufacturing.

- The metal sheet was only a few thou thick.
- The machinist adjusted the lathe to ensure the final diameter was accurate to within half a thou.

### 4. to call someone 'thou'

verb · CEFR C2 · Archaic · Literary

to use the word 'thou' when speaking to someone.

For teachers: to address a person using the pronoun 'thou'. Historically, this could imply intimacy or, conversely, a deliberate insult by refusing to use the formal 'you'.

- The judge was angry when the prisoner began to thou him.
- In the seventeenth century, to thou a social superior was considered a grave breach of etiquette and a sign of open defiance.

## Examples

- Thou art my best friend.
- In many classic poems, the writer uses thou to speak directly to a loved one or to nature.
- While modern English uses 'you' for all contexts, early modern writers used thou to signal a specific level of closeness or a lack of formal distance between speakers.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.