liaison

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. An instance or a means of communication between different groups or units of an organization, especially in the armed forces.
2. n. One that maintains communication: served as the President's liaison with Congress.
3. n. A close relationship, connection, or link.
4. n. An adulterous relationship; an affair.
5. n. Linguistics Pronunciation of the usually silent final consonant of a word when followed by a word beginning with a vowel, especially in French.

Century Dictionary and Cyclopedia

1. n. A bond of union; an intimacy; entanglement; commonly, an illicit intimacy between a man and a woman.
2. n. In the French language, the linking or joining in pronunciation of a final consonant, usually silent, to the succeeding word when that begins with a vowel: for example, vous (vö) and avez, when coming together, are pronounced vö zavā.
3. n. In cookery, a thickening, generally of beaten eggs, intended to combine or amalgamate the ingredients of a dish.

Wiktionary

1. n. Communication between two parties or groups.
2. n. Co-operation, working together.
3. n. A relayer of information between two forces in an army or during war.
4. n. A tryst, romantic meeting.
5. n. An illicit sexual relationship or affair.
6. n. A sandhi in which a normally silent final consonant is pronounced when the next word begins with a vowel.

GNU Webster's 1913

1. n. A union, or bond of union; an intimacy; an interrelationship.
2. n. An illicit sexual relation between a man and a woman; a sexual afffair.
3. n. A process of communication between parts of an organization or between two organizations acting together for a common purpose.
4. n. A person whose function it is to maintain such communication.
5. n. A pronunciation of a consonant sound that would be otherwise silent, such as the final consonant of certain French words, when the following word begins with a vowel sound.

WordNet 3.0

1. n. a usually secretive or illicit sexual relationship
2. n. a channel for communication between groups