Where does “post office telephone system” come from?

post office telephone system (English) comes from English telephone, from French téléphone, from French télé-, from Ancient Greek τῆλε, from Latin commūnicāre, from Latin commūnis, from Old Latin com(m)oinis, from Proto-Italic kommoinis — to bend; curve; arch; vault; to bow, bend, arch,...

Ancestry of “post office telephone system”, step by step

post office telephone system traces back through 3 separate lines of ancestry.

via English telephone

StepLanguageWordMeaning
1EnglishtelephoneA telecommunication device used for two-way...
2Frenchtéléphonetelephone; first-person singular present...
3Frenchtélé-tele-
4Ancient Greekτῆλεfar off, afar, far away
5Latincommūnicāre
6Latincommūniscommon, commonplace, ordinary, general, universal, shared, shared alike, of both sides, belonging to two or more together
7Old Latincom(m)oinis
8Proto-Italickommoiniscommon
9Proto-Indo-Europeanḱom-moy-ni-held in common
10Proto-Indo-Europeanḱómbeside, near, by, with
11Proto-Indo-EuropeanḱeDeictic particle, here; Post-positional...
12Middle Englishkyt
13Germankittputty certain kinds of cement used for fixing e.g. window panes
14Old High Germankuti
15Proto-West Germanickwidugum, resin
16Proto-Germanickweduzresin
17Proto-Indo-Europeangʷet-resin, gum; to say, speak
18Proto-Indo-Europeangū-to bend; curve; arch; vault; to bow, bend, arch,...

via English system

StepLanguageWordMeaning
1EnglishsystemA collection of organized things; a whole...
2Late Latinsystemaharmony; musical scale; set of celestial objects;...
3Ancient Greekσύστημαa whole made of several parts or members, system;...
4Ancient Greek-μᾰ"suffix forming a noun denoting the result of an...
5Proto-Indo-European-mn̥Creates action nouns or result nouns from verbs

via English post office

StepLanguageWordMeaning
1Englishpost officeA place concerned with the business of...
Every word from Proto-Indo-European gū-Every word from Proto-Indo-European gʷet-Every word from Proto-Germanic kweduz