monaĥo

Monaĥo is one of the words that reminds you the Esperanto core vocabulary was assembled in the 1880s by a reader of nineteenth-century European books. It is encyclopedic rather than conversational: you will meet it in history, in fiction and in translations of the classics far more often than in a conversation at a congress. That is a fair description of most of the religious vocabulary in this band, and it is not a defect. A language you can only use to order coffee is not a language.

The ĥ is the part to watch. It is the throat-scraping sound of Scottish loch and German Bach, and it is genuinely rare in Esperanto, surviving in a handful of words of Greek and Hebrew descent. Some writers substitute k and say monako, which collides messily with Monaco and is best avoided. Write the ĥ, and if your mouth will not do it, the Esperanto world will forgive a rough approximation long before it forgives the ambiguity.

Around it the affix system does the usual heavy lifting and you get three more words for free. Monaĥejo is a monastery, on the -ej- of places. Monaĥino is a nun, on the -in- of feminines. Monaĥa is monastic. None of those needs a dictionary entry, which is exactly the trade Esperanto makes: learn one root and the rest is grammar.