runtime

runtime — noun

1. the total length of time from the beginning to the end of a film, television pro

1.nounB1
Definition

the total length of time from the beginning to the end of a film, television programme, or online video

Example

The film has a runtime of just over two hours, including the closing credits.

collocation: a runtime of [time period]

Astrid checked the DVD case for the runtime before deciding whether to watch it tonight.

Common collocations
  • a runtime of
  • with a runtime of
  • short runtime
  • long runtime
  • total runtime
Synonyms
  • length

    more general; can refer to duration of any media, not just films

  • duration

    more formal; used in technical descriptions

Grammar Patterns

a runtime of [length]

with a runtime of [length]

Usage Note

Often used with 'of' or 'with' to specify the length. Common in film reviews, streaming-service descriptions, and DVD packaging.

Common Mistakes

The movie's run time is 120 minutes.
The movie's runtime is 120 minutes.
As a computing compound, 'runtime' is written as one word in modern usage.

2. the period during which a computer program is actively running and carrying out

2.nounB2
Definition

the period during which a computer program is actively running and carrying out its instructions, or the length of that period

Example

The app's runtime increased significantly after the latest update, frustrating many users.

collocation: runtime increases / decreases

Saira measured the runtime of each search algorithm to compare their efficiency.

verb + runtime: measure runtime

Common collocations
  • during runtime
  • at runtime
  • runtime error
  • runtime environment
  • runtime system
  • short runtime
  • fast runtime
Synonyms
  • execution time

    more precise; used in performance measurement contexts

  • run time

    alternative spelling; means the same thing

Antonyms
  • compile time

    the period when a program is being compiled, before it runs

Grammar Patterns

during runtime

at runtime

runtime of [program]

Usage Note

In programming, 'runtime' is often contrasted with 'compile time' or 'design time.' 'At runtime' refers to the moment when the program is actually executing, as opposed to when it is being written or compiled.

Common Mistakes

The runtime of the program took 30 seconds.
The program's runtime was 30 seconds.
'Runtime' refers to the duration itself, not to the program that takes time.

3. a software system that provides the basic tools, libraries, and environment need

3.nounC1
Definition

a software system that provides the basic tools, libraries, and environment needed for a particular computer program to be executed and run correctly

Example

To play this game on your computer, you first need to install the Java runtime.

collocation: install a / the [name] runtime

The development team chose a runtime that supports multiple operating systems for their new application.

verb + runtime: choose / select a runtime

Common collocations
  • runtime environment
  • runtime system
  • Java runtime
  • .NET runtime
  • install a runtime
  • runtime library
  • runtime engine
Synonyms

Grammar Patterns

[programming language] runtime

install a runtime

runtime for [language/platform]

Usage Note

Often referred to as a 'runtime environment' or 'runtime system.' Common examples include the Java Runtime Environment (JRE) and the .NET runtime. The term is most frequently used in discussions about programming languages and software deployment.

Common Mistakes

I need to update my runtime to watch the new video format.
I need to update my media player to watch the new video format.
A runtime is a software platform for running programs, not a media player.

Word family

Synonym discussion

Sense: noun/2

In computing, 'runtime' and 'execution time' are often used interchangeably to mean the period during which a program runs and performs its tasks, though 'execution time' is more technical and frequently appears in performance benchmarking. 'Processing time' is a broader term that can refer to any stage of computation, not just program execution. The key distinction is with 'compile time,' which refers to the phase when source code is being translated into machine code before the program runs. For example, a programmer might say 'the runtime was 2.3 seconds' when comparing algorithm speed, but 'this error is caught at compile time, not at runtime' when discussing debugging.

runtime ↗execution timeprocessing timecompile time

Common collocations

Nouns

  • runtime error
  • runtime environment
  • runtime system
  • runtime library

Phrases

  • install a runtime
  • a runtime of [time]
  • with a runtime of [time]

Prepositions

  • during runtime
  • at runtime
  • with a runtime of

Etymology

Old EnglishEnglish

Runtime is formed from 'run' and 'time.' The verb 'run' comes from Old English 'rinnan' (to flow, move swiftly), and 'time' comes from Old English 'tīma' (a period of time). The film-industry meaning of 'runtime' (the duration of a film) dates from the early 20th century, while the computing senses emerged in the mid-20th century as programming languages and operating systems developed specialised environments for executing code.