Synonyms for Overweening (same or very similar meaning)
WordNet sense 1 (unrestrained, especially with regard to feelings):
excessive, extravagant, exuberant
WordNet sense 2 (not subject to restraint):
unrestrained
WordNet sense 3 (presumptuously arrogant):
uppity
WordNet sense 4 (having or showing an exaggerated opinion of your importance, ability, etc):
immodest
From the ODE community, based on WordNet
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