I assume some of the learned folk around here are already familiar with this word, but I just discovered it, and its meaning was so unexpected I thought I’d share it:
plural columbaria \ˌkä-ləm-ˈber-ē-ə\
1: a structure of vaults lined with recesses for cinerary urns
2: a recess in a columbarium
[Latin, literally, dovecote, from columba dove]
I knew what the etymological meaning had to be, but would never have guessed the current one!
...And in fact that definition teaches me another new word, “cinerary,” referring to cremated ashes.