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*objurgate \OB-juhr-gayt\ (transitive verb) –
To express strong disapproval of; to criticize severely.
"It would be my advice to persons situated in this way, to not roll or thrash around, because this excites the interest of all the different sorts of animals and makes every last one of them want to turn out and see what is going on, and this makes things worse than they were before, and of course makes you objurgate harder, too, if you can." – Mark Twain, ‘ A Connecticut Yankee in King Arthur’s Court’
Objurgate comes from the past participle of Latin from objurgare, "to scold, to blame," from ob-, "against" + jurgare, "to dispute, to quarrel, to sue at law," from jus, jur-, "law" + -igare (from agere, "to lead").

onus \OH-nuhs\ (noun) –
1 : A burden; an obligation; a disagreeable necessity.
2 : a: A stigma. b: Blame.
3 : The burden of proof.
"The engineer was not as much fun to be with as he once was, and she thought that it might be the terrible onus of repairing the engines that weighed upon him." — Michael Flynn, ‘The Wreck of the River of Stars
Onus is adopted from Latin onus, "load, burden." The derivative Latin adjective onerosus yields English onerous, "burdensome, oppressive." The derivative Latin verb onerare has the compound form exonerare, "to free from (ex-) an onus or burden," which yields English exonerate, "to relieve, in a moral sense, as of a charge, obligation, or load of blame resting on one."

oscitancy \AH-si-tehn-si\ (noun) –
1 : Yawning or a yawn, hence
2 : the drowsiness or dullness associated with yawning.
"Jack insisted that his oscitancy came more from lack of sleep than from lack of interest."
Latin oscitare "yawn" from os- "mouth" and citare "to move". The stem cit- is also found in "cite" and "excite". It comes from Proto-Indo-European *kei(d)/koi(d) which gave English hest "command, bidding" as in "behest" and, with the suffix -n, the Greek root kin- in kin-ein "to move" that underlies "cinema" and "kinetic".

osculation \os-kyuh-LAY-shuhn\ (noun) – The act of kissing; also: a kiss.
"Within a week fifty thousand women in forty counties had pictured to themselves this osculation of intellects, and shrugged their shoulders, and decided once more that men were incomprehensible." — Arnold Bennett, ‘The Old Wives’ Tale’
Osculation comes from osculatio, "a kissing," from osculari, "to kiss," from osculum, "a little mouth, a kiss," diminutive of os, "mouth."

otiose \OH-shee-ohs; OH-tee-\ (adjective) –
1 : Ineffective; futile.
2 : Being at leisure; lazy; indolent; idle.
3 : Of no use.
"Higgins affected an otiose lifestyle that, by all appearances, was impossible to maintain. Yet maintain it he did, for many, many years."
Otiose is from Latin otiosus, "idle, at leisure," from otium, "leisure."

overweening \oh-vur-WEE-ning\ (adjective) –
1 : Overbearing; arrogant; presumptuous.
2 : Excessive; immoderate; exaggerated.
"Candace’s overweening affections were one of the many traits that Alan found so difficult to bear."
Overweening is from Middle English overwening, present participle of overwenen, "to be arrogant," from over + wenen "to ween," from Old English wenan.