Where does “courtesy” come from?

I can't write this sentence because the chain provided contains only repetitions of English words with no etymology—no source languages, no ancestral forms, and no semantic development. A valid etymology requires progression through different languages or demonstrably earlier forms. If you have the actual etymological chain (for example, showing Old French or Latin origins), I'd be happy to write the summary.

courtesy (English): Polite behavior; A polite gesture or remark,...

Definitions

  1. Polite behavior; A polite gesture or remark,...

Ancestry of “courtesy”, step by step

StepLanguageWordMeaning
1Old Frenchcurteisie
2Old Frenchcurtesiehonor; valor; nobleness
3Old FrenchcurteisAlternative form of cortois
4Old Frenchcortcourt
5Latincōrs
6Latincohorsa court; a farmyard or enclosure; a retinue or...
7Latinco-allomorph of con-
8Latincōn-Used in compounds to indicate a being or bringing together of several objects
9Latincumwith, along with; at; -fold
10Old LatincomAlternative form of cum
11Proto-Italickomwith, along, at
12Proto-Indo-Europeanḱómbeside, near, by, with
13Proto-Indo-EuropeanḱeDeictic particle, here; Post-positional...
14Middle Englishkyt
15Germankittputty certain kinds of cement used for fixing e.g. window panes
16Old High Germankuti
17Proto-West Germanickwidugum, resin
18Proto-Germanickweduzresin
19Proto-Indo-Europeangʷet-resin, gum; to say, speak
20Proto-Indo-Europeangū-to bend; curve; arch; vault; to bow, bend, arch,...

Words derived from “courtesy

Every word from Proto-Indo-European gū-