# bound

/ˈbaʊnd/ (US) · /bˈaʊnd/ (UK)

Source: https://englishreference.com/word/bound
Updated: 2026-08-15

## Senses

### 1. certain to happen

adjective · CEFR B1

very likely or certain to happen.

For teachers: certain or extremely likely to happen, often followed by an infinitive.

- If you don't study for the exam, you are bound to fail.
- Given the current economic climate, interest rates are bound to rise before the end of the fiscal year.

### 2. travelling toward

adjective · CEFR B2

travelling toward a specific place.

For teachers: heading towards a specific destination; frequently used in compound forms like 'northbound'.

- The train bound for London was delayed by twenty minutes.
- All outward-bound flights were grounded due to the volcanic ash cloud spreading across the continent.

### 3. obliged or forced

adjective · CEFR B2

forced to do something by law, duty, or a promise.

For teachers: legally or morally obliged to perform an action.

- The doctor is bound by law to keep your medical records private.
- Under the terms of the non-disclosure agreement, the former employee was bound to remain silent about the company's internal research.

### 4. restricted by conditions

adjective · CEFR C1 · Technical

unable to move or act because of a specific situation, like weather or illness.

For teachers: confined or restricted to a place or state, typically used in compounds.

- The small village was snow-bound for three days after the storm.
- The patient remained house-bound for several months while recovering from the complex surgical procedure.

### 5. to jump

verb · CEFR B2

to move quickly with large jumps.

For teachers: to move by leaps or jumps; to progress with a series of springing movements.

- The dog started to bound across the field when it saw the ball.
- The deer bounded effortlessly over the fence and disappeared into the thick forest.

### 6. to form a boundary

verb · CEFR C1 · Formal

to be the edge or limit of a place.

For teachers: to serve as a boundary for a territory or geographical area.

- The property is bounded on the north side by a small river.
- The ancient kingdom was bounded by the high mountains to the east and the vast desert to the west.

### 7. a limit

noun · CEFR B2

a limit or boundary of what is possible or allowed.

For teachers: a territorial or conceptual boundary; a limit of what is acceptable.

- His rude behavior was beyond the bounds of what is acceptable at work.
- The new scientific discovery pushed the bounds of human knowledge further than ever before.

### 8. a large jump

noun · CEFR C1 · Literary

a big, energetic jump forward.

For teachers: a large or springing leap.

- With one great bound, the cat reached the top of the wall.
- The athlete cleared the stream in a single bound, demonstrating remarkable physical strength.

### 9. mathematical limit

noun · CEFR C2 · Technical

a number that is greater or smaller than every number in a group.

For teachers: a value that is known to be greater than (upper bound) or less than (lower bound) every element in a set.

- We need to find the upper bound for this set of data.
- The algorithm calculates the lower bound of the function to determine the minimum resources required for the task.

## Examples

- There is no upper bound to how much you can learn.
- The researchers established a lower bound for the temperature required to trigger the chemical reaction.
- In computational theory, the upper bound represents the maximum amount of time or resources an algorithm requires to complete its task under the most demanding conditions.

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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.