sacrum

From Latin os sacrum (“holy bone”), a calque of Ancient Greek ἱερὸν ὀστέον (hieròn ostéon). Apparently so called either because the sacrum was the part of the animal offered in sacrifice or because of a putative belief that it is where a person's soul resides. A third explanation is that the term is a mistranslation of Ancient Greek ἱερὸν (hieròn), which has two meanings: “holy, sacred”, and “big”[1] — big being a more appropriate description of the sacrum — but compare.[2]

sacrum (plural sacra or sacrums)

1. (anatomy) A large triangular bone at the base of the spine, located between the two ilia (wings of the pelvis) and formed from vertebrae that fuse in adulthood.

• sacral

• Marcus

From sacer (“sacred, holy”).

• (Classical) IPA^(key): /ˈsa.krum/, [ˈsa.krũ]

sacrum n (genitive sacrī); second declension

1. A holy or sacred object, e.g. vessel, statue, utensil.
2. A holy or sacred place, e.g. sanctuary, shrine, temple.
3. A religious act or observance, e.g. a sacrifice, festival, rite.
4. Divine worship or religion.
   • c. 54-51 BCE, Cicero, De re publica, 2.7.13

     quo foedere et Sabinos in civitatem adscivit sacris conmunicatis et regnum suum cum illorum rege sociavit

     By this compact he admitted the Sabines into the city, gave them a participation in the religious ceremonies, and divided his power with their king.

5. The private religious rites of a family.
   • c. 51 BCE, Cicero, De Legibus, 2.9.22

     sacra privata perpetua manento

     Let private devotions be perpetually practised.

6. (only in plural) Poems (as sacred to the muse).
   • c. 8-18 AD, Ovid, Tristia, 4.10.19

     at mihi iam puero caelestia sacra placebant inque suum furtim Musa trahebat opus

     But even as a boy the heavenly poems delighted me, and the Muse was drawing me secretly to her work.

7. (only in plural, post-Augustan) Secrets, mysteries.
   • 8 AD, Ovid, Metamorphoses, 7.709

     sacra tori coitusque novos thalamosque recentes primaque deserti referebam foedera lecti

     I told Aurora of our wedding secrets and all refreshing mysteries of coition – and my first union on my now-deserted couch.

Second declension.

sacrum

1. nominative neuter singular of sacer
2. accusative masculine singular of sacer
3. accusative neuter singular of sacer
4. vocative neuter singular of sacer

• sacrum in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• sacrum in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• sacrum in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition, 1883–1887)
• sacrum in Gaffiot, Félix (1934) Dictionnaire Illustré Latin-Français, Hachette
• Carl Meissner; Henry William Auden (1894) Latin Phrase-Book‎, London: Macmillan and Co.
  • to be present at divine service (of the people): sacris adesse
    
  • to be initiated into the mysteries of a cult: sacris initiari (Quintil. 12. 10. 14)
    
  • (ambiguous) ritual; ceremonial: sacra, res divinae, religiones, caerimoniae
    
  • (ambiguous) to sacrifice: sacra, sacrificium facere (ἱερὰ ῥέζειν), sacrificare
    
  • (ambiguous) to profane sacred rites: sacra polluere et violare
    
• sacrum in William Smith, editor (1854, 1857) A Dictionary of Greek and Roman Geography, volume 1 & 2, London: Walton and Maberly