idem (not comparable)
- The same.
- Used almost exclusively in footnotes of academic or scholarly papers, especially those of the legal profession, to indicate that the source referred to in a footnote is the same as the source in the preceding footnote; usually abbreviated when so used.
- idem, ditto
- eidem (frequently in manuscripts and inscriptions)
- isdem, eisdem (rarely)
From the pronoun is (“he”) + Proto-Italic *-im (emphatic marker) (whence Sabellic *-om, Oscan 𐌝𐌔𐌝𐌃𐌖𐌌 (ísídum), 𐌄𐌔𐌝𐌃𐌖𐌌 (esídum)), from Proto-Indo-European *im (whence also Old Latin im, em), accusative singular of *éy. The s was lost and the i lengthened by compensatory lengthening.
When the ablative cases eōd, eād became eō, eā, the true forms eōd-em, eād-em were interpreted as eō-dem, eā-dem. The neuter nominative singular id-em is natural and gives earlier emem (= later eundem). The new marker -dem then served to create totidem, tantumdem, ibīdem, etc. Compare tam-en with its later doublet: tan-dem (← *tam-dem).
īdem m (feminine eadem, neuter idem)
- the same (usually with ablative)
- 29 bc. Vergil. Georgics, III
- amor omnibvs idem
- Sex is the same for all of them [viz., every form of man, beast, aquatic or winged life, and livestock]
Irregular declension. Similar to the declension of is, ea, id.
Irregular: similar to first and second declensions, except for singular genitives ending in "-ius" and singular datives ending in "-ī".
- idem in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
- idem in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
- Félix Gaffiot (1934), “idem”, in Dictionnaire Illustré Latin-Français, Paris: Hachette.
- Meissner, Carl; Auden, Henry William (1894) Latin Phrase-Book, London: Macmillan and Co.
- to hold the same views: idem sentire (opp. dissentire ab aliquo)
- to agree with a person: consentire, idem sentire cum aliquo
- to have the same meaning: idem valere, significare, declarare
- synonyms: vocabula idem fere declarantia
- to have the same political opinions: idem de re publica sentire
- Sihler, Andrew L. (1995) New Comparative Grammar of Greek and Latin, Oxford, New York: Oxford University Press
↑ idem in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
↑ De Vaan, Michiel (2008), “-dem”, in Etymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill, page 166