English Reference
verb · noun · adjective

lag

v. · n. · adj.
US /ˈɫæɡ/ UK /lˈæɡ/ lag UK spelling lagged, lags

  1. 01 B2 Upper Intermediate

    v.to move more slowly than others in a group or to fail to keep up the same speed.

    v.to fail to maintain a pace or to fall behind in movement, progress, or development. Often used with the preposition 'behind'.

    Simple

    The youngest hikers started to lag behind the rest of the group after the first hour.

    In context

    Economic growth in the northern provinces continues to lag behind the national average despite significant federal investment in infrastructure.

    Usage

    Often used as the phrasal verb 'lag behind'.

    traildallystraggle
  2. 02 B2 Upper Intermediate Informal Computing

    n.a delay between a command and a response, especially in a video game or on the internet.

    n.a period of latency between the initiation of an instruction and the resulting response in a digital system.

    Simple

    I lost the game because there was too much lag on the server.

    In context

    High network lag can render real-time collaborative software virtually unusable for remote teams.

    Usage

    Commonly used as an uncountable noun in gaming contexts.

  3. 03 C1 Advanced Technical Engineering

    v.to wrap something, like a water pipe, in a special cover to keep it warm.

    v.to provide a pipe, boiler, or similar vessel with thermal insulation by wrapping it in protective material.

    Simple

    You should lag your outdoor pipes before the first winter frost.

    In context

    The contractor was instructed to lag all exposed steam pipes to improve the building's overall energy efficiency.

    Usage

    Transitive verb requiring a direct object.

  4. 04 C2 Proficiency British EnglishSlangInformal

    n.a person who has been in prison for a long time.

    n.a person who has been convicted of a crime and served a prison sentence.

    Simple

    The old lag had spent half his life behind bars and didn't know how to live outside.

    In context

    The documentary features interviews with several old lags who describe the harsh conditions of the penal system in the 1970s.

    Teacher's tip

    Usually seen in the phrase 'old lag' to describe a career criminal or repeat offender.

  5. 05 C1 Advanced SlangTechnical Sport

    adj.a style of playing poker where you play many hands and bet aggressively.

    adj.an acronymic adjective for 'Loose-Aggressive'; a playing style characterised by playing a wide range of hands and frequent raising.

    Simple

    He is a very lag player, so you never know if he actually has a good hand.

    In context

    Adopting a LAG strategy can be highly profitable in certain tournament structures, though it carries a significantly higher risk of ruin.

    Usage

    Often written in all caps as LAG.

Usage time lag

Parents often worry that their child has forgotten math over the summer or that their reading has lagged.

Phys.org· 31 Aug 2026

Normally, when you’re playing a game this lag is imperceptible.

The Guardian· 9 Sept 2026

Of unknown origin. Possibly of North Germanic origin.

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

This entry
Level B2 · Upper Intermediate
Frequency Frequent
Updated