rarefacio

Forms

rārēfaciō (present infinitive rārēfacere, perfect active rārēfēcī, supine rārēfactum); third (-iō variant) conjugation, suppletive^[1] The passive is rārēfīō, rārēfierī.^[2][3] Lucretius also splits it in tmesis (rāreque facit).^[4][5]

Etymology

It is a compound from Latin rārus (“loose, thin”) + faciō (“to make”), “to make thin”.^[4][2][3] Wiktionary takes the first part as the adverb rārē.^[1]

Earliest recorded meaning

Lucretius uses it first, in a technical sense: fire could not be thinned out or condensed if it kept the same nature, and bodies grow old and perish when they are rarefied by flowing away.^[2][5][6]

Semantic evolution

It was almost a technical term for reducing density, either by dissolving and scattering or by loosening and opening up.^[2] Lucretius uses it of the body loosened by loss of blood and of soil made loose.^[2][3] Isidore of Seville has the passive participle of a cloud dissolving into air.^[2] The late medical writer Theodorus Priscianus also uses it,^[3] and the Latin Oribasius has the spelling rāri-.^[2]

English rarefy comes from Old French rarefier and Medieval Latin rarificare, which Etymonline traces to this verb.^[7]

Timeline

• 96–55 BC – Lucretius uses it of fire, of the body and of soil.^[2][6]
• c. 560–636 AD – Isidore of Seville describes a rarefied cloud turning into air.^[2][6]
• late 14th century – English rarefien is recorded, from Old French and Medieval Latin.^[7]

Meanings

Verb

1. To make less dense, rarefy, thin out.^[4][5][2]
2. To loosen, open up (soil, the body).^[2][3]
3. (passive) To lose density, become loose or thin.^[3]

Related words

• rarus
• facio
• English rarefy

References

1. ^ a b c d Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k Thesaurus linguae Latinae (1900–), Leipzig: Teubner; Berlin: De Gruyter; open-access ed., Munich: Bayerische Akademie der Wissenschaften
3. ^ a b c d e f Georges, Karl Ernst (1913–1918), Ausführliches lateinisch-deutsches Handwörterbuch, 8th ed., ed. Heinrich Georges, Hannover; Leipzig: Hahn
4. ^ a b c Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
5. ^ a b c Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
6. ^ a b c Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
7. ^ a b Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com