English Reference
adjective · verb · noun

bound

adj. · v. · n.
US /ˈbaʊnd/ UK /bˈaʊnd/ bound UK spelling bounding

  1. 01 B1 Intermediate

    adj.very likely or certain to happen.

    adj.certain or extremely likely to happen, often followed by an infinitive.

    Simple

    If you don't study for the exam, you are bound to fail.

    In context

    Given the current economic climate, interest rates are bound to rise before the end of the fiscal year.

  2. 02 B2 Upper Intermediate

    adj.travelling toward a specific place.

    adj.heading towards a specific destination; frequently used in compound forms like 'northbound'.

    Simple

    The train bound for London was delayed by twenty minutes.

    In context

    All outward-bound flights were grounded due to the volcanic ash cloud spreading across the continent.

  3. 03 B2 Upper Intermediate

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

    adj.legally or morally obliged to perform an action.

    Simple

    The doctor is bound by law to keep your medical records private.

    In context

    Under the terms of the non-disclosure agreement, the former employee was bound to remain silent about the company's internal research.

  4. 04 C1 Advanced Technical

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

    adj.confined or restricted to a place or state, typically used in compounds.

    Simple

    The small village was snow-bound for three days after the storm.

    In context

    The patient remained house-bound for several months while recovering from the complex surgical procedure.

  5. 05 B2 Upper Intermediate

    v.to move quickly with large jumps.

    v.to move by leaps or jumps; to progress with a series of springing movements.

    Simple

    The dog started to bound across the field when it saw the ball.

    In context

    The deer bounded effortlessly over the fence and disappeared into the thick forest.

  6. 06 C1 Advanced Formal

    v.to be the edge or limit of a place.

    v.to serve as a boundary for a territory or geographical area.

    Simple

    The property is bounded on the north side by a small river.

    In context

    The ancient kingdom was bounded by the high mountains to the east and the vast desert to the west.

  7. 07 B2 Upper Intermediate

    n.a limit or boundary of what is possible or allowed.

    n.a territorial or conceptual boundary; a limit of what is acceptable.

    Simple

    His rude behavior was beyond the bounds of what is acceptable at work.

    In context

    The new scientific discovery pushed the bounds of human knowledge further than ever before.

  8. 08 C1 Advanced Literary

    n.a big, energetic jump forward.

    n.a large or springing leap.

    Simple

    With one great bound, the cat reached the top of the wall.

    In context

    The athlete cleared the stream in a single bound, demonstrating remarkable physical strength.

  9. 09 C2 Proficiency Technical Math

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

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

    Simple

    We need to find the upper bound for this set of data.

    In context

    The algorithm calculates the lower bound of the function to determine the minimum resources required for the task.

Usage bound together

The "Dubai Tower" left the eastern port city of Ningbo on Saturday evening bound for the so-called Northern Sea Route (NSR).

Phys.org· 16 Aug 2026

All these stories contained more of that thing I had been chasing since I arrived in Amazonia: a kind of power, difficult to define, that seemed bound to the forest and its rivers.

Aeon· 20 Aug 2026
This entry
Level B2 · Upper Intermediate
Frequency Common
Updated