orotund

There is a voice of unusual roundness and fulness known as the orotund, which is indispensable to the public speaker.

Hamlet saw that pithy old Polonius was a preposterous and orotund ass.

The father of Seneca had a school of oratory where rich Roman youths were taught to mouth in orotund and gesticulate in curves.

In an orotund voice he declaims to his pupils the mighty revelations that he copied from the book.