Both Uses of

liaison

in

Ulysses by James Joyce

…when the husband frequently, after some words passed between the two concerning her relations with the other lucky mortal (he having had the pair watched), inflicted fatal injuries on his adored one as a result of an alternative postnuptial liaison by plunging his knife into her, until it just struck him that Fitz, nicknamed Skin-the-Goat, merely drove the car for the actual perpetrators of the outrage and so was not, if he was reliably informed, actually party to the ambush which, in…†
Chpt 16

…and they got on fairly well together for the sake of argument, when, neglecting her duties, she chose to be tired of wedded life and was on for a little flutter in polite debauchery to press their attentions on her with improper intent, the upshot being that her affections centred on another, the cause of many liaisons between still attractive married women getting on for fair and forty and younger men, no doubt as several famous cases of feminine infatuation proved up to the hilt.†
Chpt 16 *

Definition:

(liaison)
a person with the role of increasing communication and cooperation between two organizations; or an instance or other means of such communication