J, j, a consonant which, although originally represented by the same character as the vowel
i , was distinguished from it by the ancients themselves, Charis. p. 1 P.; Diom. p. 416 ib.; Prisc. p. 544 ib.; Don. p. 1735 ib. al. The old grammarians supposed it to lengthen a preceding vowel (but v. Roby, Gram. 1, § 143). Its pronunciation was like that of the German j (or Engfish y ) at the beginning of syllables, as jus, injuria, ejectus (Corss.). But where j occurs as a medial between two vowels, it is, according to the statement of the grammarians, to be pronounced double; wherefore, in such cases, it is also written double by many (e. g. by Cicero), as ajjo, Majja, ejjus, pejjus, etc., Quint. 1, 4, 11; Prisc. p. 545 P.; Vel. Long. p. 2219 ib. al.; and in inscriptions with a tall I. The closest relation exists between j and the vowel i , and in the course of formation and inflection they are very often interchanged: Pompejus, Pompei; Gajus, Gai; jam, etiam, quoniam; ajo, aibam. By the poets, i was often hardened into j to form position: abjete, abjetibus, for abiete, abietibus; cf. Val. Prob. p. 1432 P.; Mar. Vict. p. 2474 ib. J is related to g , as magis, major. J arises from dj or di , as Juppiter, Jovis, from Djuppiter, Djovis. J was omitted before another i in compounds of jacio with monosyllabic prepositions: abicit, adicit, obicit, for abjicit, adjicit, objicit. The preposition is regularly long ( Verg. A. 6, 421), but after the time of Ovid is sometimes shortened ( Luc. 9, 188). A diphthong is sometimes formed with the preceding vowel: reicĕ ( Verg. E. 3, 96), eicĭt ( Lucr. 3, 890). As an abbreviation, J. O. M. signifies Jovi Optimo Maximo; J. R. Juno Regina; J. V. T. Julia Victrix Togata.