Can we use "liaison" casually?

Question

Then there was the Mad Russian, who made her laugh and behaved impossibly badly and proposed to her daily. Some other shorter-lived liaisons, now forgotten. Then Henry.
— William Nicholson, Secret Intensity Of Everyday Life

In the context, the narrator says the word liaison without rendering any moral viewpoint. Though many dictionaries contain moral defects in the word, Longman Advanced American Dictionary says liaison means “a sexual relationship between two people who are not married” without any further moral angles, and Merriam-Webster says it means “a close bond or connection”.

Can we use the word liaison casually, like in the example?

Answer 1

The OED provides in its sense 2 both an older, generic subsense and a newer, specific subsense.

The generic one is:

a. gen. An intimate relation or connexion.

while the specific one is:

b. spec. An illicit intimacy between a man and a woman.

(Although today, one should probably write that as an illicit intimacy regardless of the sex of the two parties: man and man, man and woman, woman and man, woman and woman.)

However, both debuted in the early 19^th century, so it is probably not right to claim the one the elder use. There is a 17^th century sense related to cooking, and also two more 19^th century senses: one related to phonetics and the other a military term. The military liaison sense in particular is attractive, because there is no sexual overtone there at all.

I think you can sometimes get away with it. It just depends on context.

Answer 2

The sexual connotation of the word liaison is not its prime meaning. We speak all the time of liaisons between governments and their bureaus and departments, and it is unlikely that these are meant in a sexual sense.

liaison
n
1. communication and contact between groups or units
2. (modifier) of or relating to liaison between groups or units a liaison officer
3. a secretive or adulterous sexual relationship
4. (Military) the relationship between military units necessary to ensure unity of purpose
5. (Linguistics / Phonetics & Phonology) (in the phonology of several languages, esp French) the pronunciation of a normally silent consonant at the end of a word immediately before another word commencing with a vowel, in such a way that the consonant is taken over as the initial sound of the following word. Liaison is seen between French ils (il) and ont (ɔ̃), to give ils ont (il zɔ̃)
6. (Cookery) any thickening for soups, sauces, etc., such as egg yolks or cream

^Collins

Answer 3

Yes, you can use it casually without worrying about the sexual connotations unless the context forces them front and center. The military and diplomatic services of many countries have liaison officers, and their jobs have nothing to do with illicit sexual relationships. Even the famous film Les Liaisons Dangereuses kept the novel's title word dangerous to indicate the sexual nature of the liaisons depicted in the work.