The most common and most likely answer to this crossword clue is the 8 letter word SACRARIA
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More clues leading to the result SACRARIA
Buddy explains!
The straight part
We know that "Where relics are housed" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case where relics are housed = sacraria.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SACRARIA mean?
SACRARIA noun- In Ancient Rome, a place where sacred objects were kept, either in a temple (the adytum) or in a house (holding the penates)
- The area surrounding the altar of a Christian church; the sanctuary or piscina. Sometimes specifically a drain directly to the earth, perhaps including reference to a basin, for washing vessels from consecration.
- The complex sacrum of any bird.