V has the closest affinity to the vowel u, and hence, in the course of composition and inflection, it often passed into the latter: solvo, solutum, from solvĭtum, solŭĭtum; caveo, cautum, from cavitum; fautor, from faveo; lautum, from lavo; nauta, from navita; audeo, cf. avidus; neu, seu, from neve, sive; tui, cf. Sanscr. tvam; sui, Sanscr. sva-; suavis, Sanscr. svadus, and is resolved into it by the poets from prosodial necessity: silŭa (trisyl.) for silva; dissŏlŭo, evŏlŭam (quadrisyl.), for dissolvam, evolvam; dissŏlŭenda, evolŭisse (quinquasyl.), for dissolvenda, evolvisse, etc., just as, for the same cause, although less freq., u passed into v: gēnva, tēnvis (dissyl.), for gēnŭa, tĕnŭis; tēnvĭa, tēnvĭus (trisyl.), for tĕnŭĭa, tĕnŭĭus.—For the affinity of v to b, v. the letter B.
V as a medial between two vowels was very freq. elided, esp. in inflection, and the word underwent in consequence a greater or less contraction: amavisti, amāsti; deleverunt, delērunt; novisti, nōsti; audivisti, audīsti, or audiisti; siveris, siris, or sieris; obliviscor, oblitus; dives, dis; aeviternus, aeternus; divitior, ditior; bovibus, bubus, etc.; providens, prudens; movimentum, momentum; provorsus, prorsus; si vis, sis; si vultis, sultis; Jovis pater, Juppiter; mage volo, mavolo, malo; non volo, nolo, etc. An example of the elision of v without a further contraction of the word is found in seorsus, from sevorsus (v. seorsus).—This etymological suppression of v is to be distinguished from its purely orthographical omission before or after u in ancient MSS. and inscriptions, as serus for servus, noum for novum, festius for festivus, Pacuius for Pacuvius; cf. the letters J and Q.—V is sometimes elided after a mute: dis for dvis from duo; likewise after s: sibi for svibi (from su-ibi); sis, sas, sos, for suis, suas, suos; sultis for si vultis; so Lat. si corresponds to Umbr. sve and Osc. svai; v. esp. Corss. Ausspr. 1, p. 310 sqq.
As an abbreviation, V (as the sign of the consonant) stands for vir, vivus, vixit, voto, vale, verba, etc.; V. C., or also VC., vir clarissimus; VCP., voti compos posuit; V. V., virgo Vestalis; V. F. Q. D. E. R. F. P. D. E. R. I. C., verba fecerunt. Quid de eā re fieri placeret, de eā re ita censuerunt.—As a numeral, the letter V stands for half of the geometrical cross X or ten, Zumpt, Gr. § 115 Anm. 1.