Orotund

Orotund (pronounced awr-uh-tuhnd or ohr-uh-tuhnd)

(1) Of the voice or speech, characterized by strength, fullness, richness, and clearness.

(2) Of a style of speaking, pompous or bombastic.

1792:  A portmanteau word from the Latin phrase ōre rotundō (literally "with round (or rounded) mouth"), the meaning being “in well-rounded phrases", meant usually as a compliment but used also by the hoi polloi to poke fun at toffs, examples of which are found in Roman graffiti.  Construct was ōre (from os, oris) (the mouth) + rotundō (round); rotundō was an alternative form of rotundus (from rotō (turn around, revolve)) + undus.  The suffix undus is interesting.  It’s possibly from Proto-Italic ontnos, syncopated from ontinos, from the primitive Indo-European ont (participial suffix) + i (suffix of action) + nós (adjective-forming suffix).  The undus suffix, first associated with intransitive deponent verbs as sequor (secundus), orior (oriundus), lābor (lābundus), and other relics, then transited from a derivative to an inflectional category and the gerundive assumed its canonical shape and function.  It improved the language.  The derivation from gerundive to the later gerund could then be as easy as an abstraction from ad librum legendum (to read the book) to ad legendum (to read).

In his Dictionary of Modern English Usage (1926), Henry Fowler (1858–1933), decried the use of orotund as a display of pride of knowledge, something of which he seldom approved.  Appalled also at the bad formation, of orotund he noted:

“The odd thing about the word is that its only currency, at least in its non-technical sense, is among those who should most abhor it, the people of sufficient education to realize its bad formation; it is at once a monstrosity in its form & a pedantry in its use.”

That seemed harsh but he was prepared to concede if  "elocutionists and experts in voice production like it as a technical term, they are welcome to it".  Certainly synonyms abound: For (1) there’s deep, sonorous, strong, powerful, full, full-toned, rich, fruity, clear, round, esonant, ringing, loud, booming, imposing, ringing, resounding, reverberant, thundering, thunderous & rumbling and for (2) there’s pompous, pretentious, affected, mannered, fulsome, grandiose, ornate, over-elaborate, overblown, flowery, florid, flamboyant, inflated, high-flown, high-sounding, magniloquent, grandiloquent, declamatory, rhetorical, oratorical, theatrical, actorly, rotund, bombastic, overwrought, overdone, overripe, convoluted, turgid, highfalutin, purple, raretumid, euphuistic, aureate, ossianic, fustian & hyperventilated.

Soviet Union 5 kopek Kim Philby memorial postage stamp issued in 1990.

Still, there were those who found it handy.  The well-spoken Kim Philby (1912-1988), the MI6 double agent who defected to Moscow in 1963, was more anxious than most to seem part of the proletariat and, apparently without irony, used orotund to describe those with pronunciation he thought a bit too received.

Lindsay Lohan, 2010 MTV Movie Awards, Los Angeles, June 2010.

There's no history in English of ōre rotundō or orotund being used literally (round (ie open) mouthed) and to the Romans the phrase was always figurative.  Presumably one could apply it thus although, from his grave, Henry Fowler would not approve.