rifuĝejo

Decode it before you memorise it. Rifuĝi is to take refuge, to get yourself somewhere safe. -Ej- is the place suffix, the one that turns an activity into the building it happens in: lerni and lernejo, preĝi and preĝejo, kuiri and kuirejo. So a rifuĝejo is the taking-refuge place, and the word needs no separate learning at all.

One word, a very wide range of buildings. English has to choose between refuge, shelter, hostel, sanctuary, hide-out and bolt-hole; Esperanto has this one noun and lets the sentence say which. A mountain hut for walkers is a monta rifuĝejo; a wartime cellar is a kontraŭbomba rifuĝejo; a hostel for people with nowhere else is a rifuĝejo por senhejmuloj; a nature reserve is a rifuĝejo por birdoj. If you want a specific one, compound it. If you do not, rifuĝejo on its own is perfectly clear.

Do not confuse it with the legal word. Azilo is asylum, the status a country grants; rifuĝejo is a roof. Nor is it the person: the rifuĝi page sets out the participle nouns, and a refugee is a rifuĝinto, one who has fled. Three separate words for three separate things, and Esperanto keeps them apart more tidily than English does.

The register is neutral, and worth keeping neutral. In Esperanto community writing rifuĝejo is a plain factual noun, the sort of word that turns up on a signpost. It carries no pity and no sneer, which is exactly what you want from it.