signum

Learned borrowing from Latin signum. Doublet of sign.

• IPA^(key): /ˈsɪɡnəm/

signum (plural signa or signums)

1. A sign, mark, or symbol.
2. (history) A medieval tower bell used particularly for ringing the eight canonical hours.^[1][2]

   Synonym: signum bell

3. (mathematics) A function that extracts the sign of a real number x, yielding −1 if x is negative, +1 if x is positive, or 0 if x is zero.

   Synonyms: signum function, sign function

• signum manus

• musing

Latin Wikipedia has an article on:

signum

Wikipedia ^la

From Proto-Italic *seknom, from Proto-Indo-European *sek- (“to cut”) or *sekʷ- (“to follow”).

• (Classical Latin) IPA^(key): /ˈsiɡ.num/, [ˈs̠ɪŋnʊ̃ˑ]
• (modern Italianate Ecclesiastical) IPA^(key): /ˈsiɲ.ɲum/, [ˈsiɲːum]

signum n (genitive signī); second declension

1. visible indication: sign, mark, signal

   Synonyms: index, indicium

   signa conferre cum aliquo ― to go for fight with someone

2. seal, signet
3. emblem, ensign
4. watchword
5. symptom, prognostic
6. miracle, miraculous work, sign
7. statue, figure
   • 70 BCE, Cicero, In Verrem 2.1.46:

     Delum venit. Ibi ex fano Apollinis religiosissimo noctu clam sustulit signa pulcherrima atque antiquissima, eaque in onerariam navem suam conicienda curavit.

     He went to Delos. There, from that holiest temple of Apollo, at night, he secretly took away the most beautiful and ancient statues, and made sure to have them loaded on board his own ship.

8. (chiefly poetic) constellation; sign in the heavens, heavenly sign
   • 29 BCE, Virgil, Georgics 1.239:

     ōrdō signōrum

     the Zodiac signs

   • 8 CE, Ovid, Fasti 4.12:

     lāpsaque sub terrās ortaque signa canō

     [...] and the constellations having sunk beneath the earth and arisen, I sing.

9. (Medieval Latin) signum (medieval tower bell used particularly for ringing the 8 canonical hours)
10. (Medieval Latin) the cross of Jesus Christ & Christianity.
    • 12th c., Honorius Augustodunensis, Gemma animae 1.57, (from du Cange, Glossarium mediæ et infimæ latinitatis, page 482a):

      Tribus autem digitis signa facimus, quia Trinitatem exprimimus.

      We perform these signings of the cross with three fingers, because we represent the Trinity with it.

Second-declension noun (neuter).

• signum interrogationis (?)
• signum exclamationis (!)
• signum citationis („“)
• signum divisionis (- resp. ⸗, to divide)
• signum subunionis (- resp. ⸗, to unite)
• signum productionis (¯)
• signum correptionis (˘)

• insignis
• sigillum
• signifex
• significō
• signō

• signātūra

• “signum”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• “signum”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• signum in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
• Carl Meißner, Henry William Auden (1894) Latin Phrase-Book‎^[1], London: Macmillan and Co.
  • (ambiguous) to follow the standards: signa sequi (opp. a signis discedere, signa relinquere)
    
  • to demand loudly the signal to engage: signum proelii (committendi) exposcere (B. G. 7. 19)
    
  • to give the signal to engage: signum proelii dare
    
  • to fight hand-to-hand, at close quarters: collatis signis (viribus) pugnare
    
  • (ambiguous) statues and pictures: signa et tabulae (pictae)
    
  • (ambiguous) to begin the march, break up the camp: signa ferre, tollere
    
  • (ambiguous) to deviate, change the direction: signa convertere (B. G. 1. 25)
    
  • (ambiguous) to follow the standards: signa sequi (opp. a signis discedere, signa relinquere)
    
  • (ambiguous) to pluck up the standards out of the ground (to begin the march): signa convellere (vid. sect. XVI. 6, note signa...)
    
  • (ambiguous) to attack the enemy: signa inferre in hostem
    
  • (ambiguous) to come to close quarters: signa conferre cum hoste
    
  • (ambiguous) the retreat is sounded: signa receptui canunt
    
• “signum”, in Harry Thurston Peck, editor (1898), Harper's Dictionary of Classical Antiquities, New York: Harper & Brothers
• “signum”, in William Smith et al., editor (1890), A Dictionary of Greek and Roman Antiquities, London: William Wayte. G. E. Marindin
• Walther von Wartburg (1928–2002) “sĭgnum”, in Französisches Etymologisches Wörterbuch, volumes 11: S–Si, page 605

• Dizionario Latino, Olivetti