English Reference
noun

completion

n.
US /kəmˈpɫiʃən/ UK /kəmplˈiːʃən/ com·ple·tion UK spelling completions

  1. 01 B2 Upper Intermediate

    the act of finishing a task, project, or process.

    the act of finishing something or the state of being finished; often used in project management and academic contexts.

    Simple

    The project is nearing completion after six months of hard work.

    In context

    The successful completion of the clinical trials paved the way for the drug's approval by the regulatory authorities.

    Usage

    Often follows the prepositions 'on' or 'upon'.

    conclusionfinalizationfinish
  2. 02 C1 Advanced FormalTechnical Law

    the final stage of buying a house or land when the ownership officially changes.

    the final stage of a property transaction where the legal title is transferred and the balance of the purchase price is paid.

    Simple

    We should get the keys to our new home on the day of completion.

    In context

    The solicitor confirmed that completion had taken place at noon, allowing the buyers to take immediate possession of the premises.

    Usage

    Commonly used in the phrase 'date of completion'.

  3. 03 B2 Upper Intermediate American English Sport

    a successful catch of a forward pass in American football.

    a forward pass that is successfully caught by an eligible receiver.

    Simple

    The quarterback had twenty completions during the game.

    In context

    The veteran quarterback maintained a high completion percentage despite the aggressive defensive pressure from the opposing linebackers.

    incompletion
  4. 04 C1 Advanced Technical Computing

    a feature that finishes a word or command for you as you type.

    a software feature that predicts and finishes the rest of a word or command being entered by the user.

    Simple

    The code editor provides automatic completion for many programming languages.

    In context

    The command-line interface supports tab completion, which significantly reduces the time required to navigate complex directory structures.

    autocomplete
  5. 05 C2 Proficiency Technical Math

    the act of adding points to a space so that every sequence has a limit.

    the process of making a metric space complete by adding points, or the resulting space itself.

    Simple

    The real numbers can be seen as the completion of the rational numbers.

    In context

    In functional analysis, the completion of a normed vector space is a Banach space where every Cauchy sequence converges.

Usage successful completion

The first, MV Glen Sannox, was finally delivered in November 2024, while MV Glen Rosa is due for completion by the end of this year.

BBC News· 18 Aug 2026

So the service providers must clearly define quality-first service: more analysis, a better expected result and a disclosed completion window.

Phys.org· 19 Aug 2026

Borrowed from Latin completio, completionem, from complere (“to fill up, complete”); comparable to English complete + -ion.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin completio
Level B2 · Upper Intermediate
Frequency Common
Updated