οὐσία

• οὐσίη (ousíē) — Ionic
• ἐσσία (essía), ὠσία (ōsía) — Doric

From ὤν, οὖσᾰ, ὄν (ṓn, oûsa, ón, “being”), the present participle of εἰμῐ́ (eimí) (“to be”), + -ῐ́ᾱ (-íā, abstract noun suffix).^[1]

οὐσίᾱ • (ousíā) f (genitive οὐσίᾱς); first declension

1. that which is one's own, one's substance, property
   • 497 BCE – 405 BCE, Sophocles, Women of Trachis 911
   • 416 BCE, Euripides, Herakles 337
   • 412 BCE, Euripides, Helen 1253
   • 391 BCE, Aristophanes, Assemblywomen 729
   • 445 BCE – 380 BCE, Lysias, On the Confiscation of the Property of the Brother of Nicias 17
   • 380 BCE, Plato, The Republic 551B
   • 440 BCE – 390 BCE, Andocides, On the Mysteries 74
   • 445 BCE – 380 BCE, Lysias, On the Refusal of a Pension 11
   • 342 BCE – 291 BCE, Diphilus, Collected Works 32.7
   • Anaxipp. 1.32
   • 440 BCE – 390 BCE, Andocides, On the Mysteries 118
   • 445 BCE – 380 BCE, Lysias, Against Diogeiton 4
2. (philosophy) Synonym of φύσις (phúsis) stable being, immutable reality
   • 470 BCE – 385 BCE, Philolaus, Collected Works 11
   • 380 BCE, Plato, The Republic 359A–B
   • 350 BCE, Aristotle, Parts of Animals 646A.25
   • 371 BCE – 287 BCE, Theophrastus, Enquiry into Plants 6.1.1
   • 360 BCE, Plato, Timaeus 29C
   • 360 BCE, Plato, The Sophist 232C
   • 428 BCE – 347 BCE, Plato, Laws 966E
   • 350 BCE, Aristotle, Parts of Animals 641B.32
   • 384 BCE – 322 BCE, Aristotle, Metaphysics 1003B.7
   • 366 BCE – 348 BCE, Plato, Theaetetus 185C
   1. substance, essence
      • 399 BCE, Plato, Euthyphro 11A
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1003B.7
      • 384 BCE – 322 BCE, Aristotle, Posterior Analytics 83A.24
      • 350 BCE, Aristotle, Parts of Animals 643A.27
      • 384 BCE – 322 BCE, Aristotle, On the Soul 402A.8
   2. true nature of that which is a member of a kind
      • 428 BCE – 347 BCE, Plato, Phaedo 65D
      • 428 BCE – 347 BCE, Plato, Phaedo 92D
      • 384 BCE – 322 BCE, Aristotle, Posterior Analytics 90B.30
      • 380 BCE, Plato, The Republic 509B
      • 428 BCE – 347 BCE, Plato, Phaedrus 245E
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1017B.22
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1031A.1
   3. the possession of such a nature, substantiality
      • 380 BCE, Plato, The Republic 509B
   4. (in the concrete) the primary real, the substratum underlying all change and process in nature
      • 384 BCE – 322 BCE, Aristotle, Fragments 208
      • 350 BCE, Aristotle, On the Heavens 298A.29
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1017B.10
      • 350 BCE, Aristotle, On the Heavens 298B.3
      • 360 BCE, Plato, The Sophist 246A
   5. (logic) substance as the leading category
      • 384 BCE – 322 BCE, Aristotle, Categories 1B.26
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1045B.29
      • 384 BCE – 322 BCE, Aristotle, Categories 2B.5
      • 384 BCE – 322 BCE, Aristotle, Categories 2A.15
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1035B.29
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1043A.30
      • 384 BCE – 322 BCE, Aristotle, On the Soul 412A.16
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1037A.5
      • 384 BCE – 322 BCE, Aristotle, On the Soul 412A.19
      • 384 BCE – 322 BCE, Aristotle, Metaphysics 1035B.15
      • 384 BCE – 322 BCE, Aristotle, Posterior Analytics 87A.36
   6. (various uses after Plato and Aristotle)
      • c. 334 BCE – c. 262 BCE, Zeno of Citium, Stoic 1.24
      • Polystr. 12
      • 204 CE – 270 CE, Plotinus, Collected Works 2.4.5
      • 204 CE – 270 CE, Plotinus, Collected Works 2.6.1
      • 204 CE – 270 CE, Plotinus, Collected Works 4.7.8
      • 204 CE – 270 CE, Plotinus, Collected Works 6.1.2
   7. Pythagorean name for I
      • Theol., Ar. 6
3. name of a plaster
   • Aet. 15.15.45
4. a fire-resisting substance
   • 498 CE – 518 CE, Zosimus, Alch. 168B
5. (in magic) a material thing by which a connection is established between the person to be acted upon and the supernatural agent

• Greek: ουσία (ousía)
• → Arabic: أُوسِيَّة (ʔūsiyya)

• “οὐσία”, in Liddell & Scott (1940) A Greek–English Lexicon, Oxford: Clarendon Press
• “οὐσία”, in Liddell & Scott (1889) An Intermediate Greek–English Lexicon, New York: Harper & Brothers
• οὐσία in Bailly, Anatole (1935) Le Grand Bailly: Dictionnaire grec-français, Paris: Hachette
• G3776 in Strong, James (1979) Strong’s Exhaustive Concordance to the Bible
• οὐσία in Trapp, Erich, et al. (1994–2007) Lexikon zur byzantinischen Gräzität besonders des 9.-12. Jahrhunderts [the Lexicon of Byzantine Hellenism, Particularly the 9th–12th Centuries], Verlag der Österreichischen Akademie der Wissenschaften
• Woodhouse, S. C. (1910) English–Greek Dictionary: A Vocabulary of the Attic Language‎, London: Routledge & Kegan Paul Limited.
  • affair idem, page 16.
  • being idem, page 72.
  • competence idem, page 151.
  • essence idem, page 283.
  • existence idem, page 292.
  • fortune idem, page 340.
  • inheritance idem, page 440.
  • possession idem, page 628.
  • property idem, page 653.
  • reality idem, page 676.
  • substance idem, page 832.