My dictionary defines étagère as bookcase or shelf. I gave bookcase and DL said shelf.
"shelf" = "étagère"
"bookcase" = "bibliothèque"
But a bookcase is a kind of etagere in French that's why your dictionary said that. In reality we are not so precise. All our furniture are "étagère" or "placard" (closet) and we rarely use precise words like bookcase.
Thanks, puopjick. That's really useful. So, if we use etagere for flat or open-fronted furniture and placard for anything with a door, we should be able to navigate our way around a French room?
Basically yes, etagere for open-fronted furniture, placard for small or medium furniture with a door or for the true closet, armoire for big furniture with a door or just meuble when the furniture is more sophisticate or you are too lazy to use one of the previous one and it's perfect^^
It's a funny thing because we say that just because we are too lazy to use the precise word, so instead of saying "mets le dans la bibliothèque", we say "mets le dans le meuble à gauche dans le fond de la chambre" (because you have a lot a furniture in a house so you need some precisions...) and then at the end you have a longer and more complicate sentence...
I think you got to something important there: that the French avoid the long complicated and more precise wording to get to a shorter, quicker to say, wording, but losing precision. If the language were both precise and shorter, then there would be less flou and still easy to use.