dorsum

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dorsum

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Borrowing from Latin dorsum (“the back”).

• (Received Pronunciation) IPA^(key): /ˈdɔː.səm/
• (General American) IPA^(key): /ˈdɔɹ.səm/

dorsum (plural dorsa)

1. (anatomy) The back or dorsal region on the surface of an animal.

   Synonym: back

   1. The back of the tongue, used for articulating dorsal consonants.
   2. The top of the foot or the back of the hand.
2. (geology) A ridge on a hill, or on the surface of a planet or moon.
3. (astronomy) Theta Capricorni, a star on the back of the Goat.

• dorsal, dorsumal
• dorsum sellae

• “dorsum”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.
• “dorsum”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.

• dromus, dumsor

• (Classical Latin) IPA^(key): /ˈdor.sum/, [ˈd̪ɔrs̠ʊ̃ˑ]
• (modern Italianate Ecclesiastical) IPA^(key): /ˈdor.sum/, [ˈd̪ɔrsum]

From Proto-Italic *dorsom, probably derived from deorsum (“downwards”) < *dēvorsum, with a semantic shift from "turned away from" > "back". Ramat notes that the two terms' contemporaneous use suggests that one was not a phonetic development of the other;^[1] however, de Vaan explains this as a case of lexical differentiation in the written and by extension spoken forms.^[2] A potential connection with a Proto-Celtic *dros-man, giving Old Irish druimm (“back, ridge”), is unclear.

• dorsus
• dossum (late, proscribed)

dorsum n (genitive dorsī); second declension

1. (anatomy) the back (part of the body between the neck and buttocks)
2. (transferred sense) the ridge, summit of a hill, a reef in the sea; any elevation
   • 29 BCE – 19 BCE, Virgil, Aeneid 1.108–110:

     Trīs Notus abreptās in saxa latentia torquet —
     saxa vocant Italī mediīs quae in flūctibus ārās —
     dorsum immāne marī summō [...].

     Three [ships] were taken away [by] the Southwind, hurled into hidden rocks – rocks the Italians call the Altars, which [are] in the middle of the waves – a vast reef near the surface of the sea.
     (This “vast reef” or “huge ridge” posed a hidden danger; understood more imaginatively, a “monstrous spine” of rock destroyed the ships. Notus was the Greek south wind.)

   • 27 BCE – 25 BCE, Titus Livius, Ab Urbe Condita I.3:

     Quae ab situ porrectae in dorso urbis Longa Alba appellata

     This [new city] was named Alba Longa, from its position, as it lay stretched out along the ridge

Second-declension noun (neuter).

• Vulgar Latin: dossum (see there for further descendants)
• → Catalan: dors
• → English: dorsum
• → Esperanto: dorso
• → Italian: dorso
• → Portuguese: dorso
• → Spanish: dorso

• “dorsum”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• “dorsum”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• dorsum 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)
• dorsum in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.

See the etymology of the corresponding lemma form.

dorsum (not comparable)

2. Alternative form of deorsum (“down”)

• “deorsum” in the Thesaurus Linguae Latinae (TLL Open Access), Berlin (formerly Leipzig): De Gruyter (formerly Teubner), 1900–present