It is anyone’s guess: the word “appointment” must be related to “point,” right?
Indeed. As it would be expected, it comes from French. The original French verb appointer comes from a point (“to the point”).
How do you say “appointment” in Armenian?
It depends on the meaning, since there is not a single word.
If you are going with the original meaning of “assigning a position to someone,” then you have the word նշանակում (nushanagoom), whose root is the noun նշանակ (nushanag “sign; signal”), and has a structure similar to the French word désignation (dé-sign-ation “appointment”) and the English word “assignment” (as-sign-ment, which used to mean “appointment to office” starting in the fifteenth century).
If you are having a scheduled visit to a doctor’s office or some kind of official business, then you cannot say Ես նշանակում մը ունիմ (Yes nushanagoom muh oonim (“I have a …”), because that would be a clumsy attempt at translating the word with a dictionary without thinking about the meaning. The Armenian language has created a different word for that, combining the concepts of “time” and “fixing,” which is what an appointment is. The result is ժամադրութիւն (jamatrootioon), and then you may say Ես ժամադրութիւն մը ունիմ ատամնաբոյժին հետ (Yes jamatrootioon muh oonim adamnapoojin hed “I have an appointment with the dentist”), and everything will be all right, both your appointment and your command of the language.
Talking about clumsy attempts, if you want to make an appointment, please use your common sense. You cannot build an appointment in English (one of the meanings of “make”), right? Then, do not think that you are entitled to do it in Armenian and then you can happily say: Ես ժամադրութիւն մը շինեցի (Yes jamatrootioon muh sheenetsee). That does not mean “I made an appointment,” but “I built an appointment”! Unless an appointment is a Lego toy, rest assured that you have simply killed the language with a single shot…