English Reference
noun

liaison

n.
US /ˈɫeɪˌzɑn/ UK /liːˈeɪzɒn/ li·ai·son UK spelling liaison's, liaison's

  1. 01 B2 Upper Intermediate

    communication between different groups or people so they can work together well.

    communication or cooperation which facilitates a close working relationship between people or organizations.

    Simple

    There is close liaison between the police and the local community.

    In context

    The success of the project depended on effective liaison between the engineering department and the marketing team during the initial design phase.

  2. 02 B2 Upper Intermediate

    a person whose job is to help two different groups communicate and work together.

    an individual who acts as a link to assist communication or cooperation between groups of people.

    Simple

    She acts as a liaison between the school and the parents.

    In context

    The embassy appointed a military liaison to coordinate the joint rescue efforts with the local authorities.

  3. 03 C1 Advanced Formal

    a secret romantic or sexual relationship between two people.

    a secret sexual relationship between two people who are not married to each other.

    Simple

    The book tells the story of a dangerous liaison between two spies.

    In context

    The politician's career was nearly ruined when the press uncovered his brief liaison with a former staff member.

  4. 04 C2 Proficiency Technical Cooking

    a mixture, often made of egg yolks and cream, used to thicken a sauce.

    a binding or thickening agent for soups or sauces, typically consisting of egg yolks and cream.

    Simple

    Add the liaison to the soup at the very end to make it creamy.

    In context

    The chef carefully tempered the liaison before whisking it into the velouté to ensure the egg yolks did not curdle.

    thickenerbinder
  5. 05 C2 Proficiency Technical

    the way some words are joined together when spoken, especially in French.

    the sounding of a normally silent final consonant before a following vowel or 'h' mute.

    Simple

    In French, the 's' in 'les' is heard because of liaison when the next word starts with a vowel.

    In context

    The student struggled with the rules of mandatory liaison, often failing to link the final consonant of the adjective to the following noun.

    linkingsandhi

Usage liaison officer

His family have been informed and are being supported by a family liaison officer, the force added.

The Guardian· 15 Aug 2026

For example, there are huge numbers of vacancies in victim liaison roles, so we are not sure how the extra victim contact scheme work will be done.

The Guardian· 11 Aug 2026

Borrowed from French liaison (“binding”), from Latin ligātiō (stem ligātiōn-; whence the English doublet ligation), derived from ligō (“I bind”), from Proto-Indo-European *leyǵ- (“to bind”).

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

This entry
Origin ine-pro *leyǵ-
Level C1 · Advanced
Frequency Frequent
Updated