The Collaborative International Dictionary of English v.0.48:
Viva voce \Vi"va vo"ce\ (v[imac]"v[.a] v[=o]"s[-e]). [L.] By word of mouth; orally. [1913 Webster]WordNet (r) 3.0 (2006):
viva voce adv 1: orally; "I heard it viva voce" [syn: by word of mouth, viva voce] n 1: an examination conducted by spoken communication [syn: oral, oral exam, oral examination, viva voce, viva]