Mammoth Uncensored Word List:
24 - 16 letter words starting with v

vaingloriousness vascularizations vasoconstriction vasoconstrictive vasoconstrictors vegetativenesses ventriculoatrial ventriculography verifiablenesses vesicointestinal vicepresidential victoriousnesses videoconferenced videoconferencer videoconferences vigintilliardths villainousnesses vindictivenesses virginitiphobics vociferousnesses voluminousnesses voluptuousnesses vulnerablenesses vulvovaginitises