kortegano

Peel it in the order it was built. Korto is a yard, the space enclosed by a building. Add -eg-, the augmentative, and you get kortego: not a big yard but a royal court, the household and the ceremony that fills it. Then add -an-, the member suffix, and you get a member of that household: a courtier. Nothing was borrowed except the first four letters, and English arrived at courtier by very nearly the same route several centuries earlier.

-An- is one of the best machines in the language. It turns any group into its members and it never asks permission: klubano a club member, urbano a townsperson, vilaĝano a villager, samideano a fellow believer, kristano a Christian, respublikano a republican, ŝipano a crew member, familiano a member of the family. Learn the suffix once and you have several hundred words. It pairs naturally with -estr-, which gives you the person in charge of the same thing, so a kortegestro runs the court that a kortegano merely lives in.

The register is historical, and slightly sceptical. A kortegano is a courtier in the full sense English gives the word: somebody whose occupation is being present. Korteganeco is the condition, kortega is the adjective, and kortegumi would be to hang about a court to no purpose, which is the sort of thing -um- is for.