liaison

noun

• 1communication or cooperation which facilitates a close working relationship between people or organizations:the head porter works in close liaison with the reception office
• [count noun] a person who acts as a link to assist communication or cooperation between people:he’s our liaison with a number of interested parties
• [count noun] a sexual relationship, especially one that is secret or illicit: she abandoned her loyalty to her absent husband in favour of a sexual liaison with William

• 2the binding or thickening agent of a sauce, often based on egg yolks.

• 3 Phonetics (in French and other languages) the sounding of a consonant that is normally silent at the end of a word, because the next word begins with a vowel.
• introduction of a consonant between a word that ends in a vowel and another that begins with a vowel, as in English law and order.