
1) Inside 2) Interior 3) The innermost parts 4) Things kept secret
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inmost parts of a building or temple; innermost secrets
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http://phrontistery.info/p.html

• (n. pl.) Hidden things or secrets; privacy; sanctuary; as, the sacred penetralia of the home. • (n. pl.) The recesses, or innermost parts, of any thing or place, especially of a temple or palace.
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http://thinkexist.com/dictionary/meaning/penetralia/
Pen`e·tra'li·a noun plural [ Latin , from
penetralis penetrating, internal. See
Penetrate .]
1. The recesses, or innermost parts, of any thing or place, especially of a temple or palace.
2. Hidden things or secrets; privacy; sanctuary; as, the sacred
penetrali...Found on
http://www.encyclo.co.uk/webster/P/46

The penetralia are the private rooms of a house. In the Roman temples, the penetralia was the part of the temple where only the priest was allowed to enter and where the sacred images were stored.
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[
n] - the innermost parts
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http://www.webdictionary.co.uk/definition.php?query=penetralia
noun the innermost parts
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https://www.encyclo.co.uk/local/20974
No exact match found.