from The Century Dictionary.
- To think too highly or confidently, especially of one's self; be arrogantly conceited; presume: now chiefly in the present participle.
- To make conceited or arrogant.
from the GNU version of the Collaborative International Dictionary of English.
- transitive verb To think too highly or arrogantly; to regard one's own thinking or conclusions too highly; hence, to be egotistic, arrogant, or rash, in opinion; to think conceitedly; to presume.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- verb ergative To think too
highlyor arrogantly of (oneself).
- verb To make or render
- verb proscribed To
from Wiktionary, Creative Commons Attribution/Share-Alike License
 Magna petis Phaeton et quae non viribus istis, &c., as James and John, the sons of Zebedee, did ask they knew not what: nescis temerarie nescis; thou dost, as another Suffenus, overween thyself; thou art wise in thine own conceit, but in other more mature judgment altogether unfit to manage such a business.
Some are too partial, as friends to overween, others come with a prejudice to carp, vilify, detract, and scoff;
"I am the servant of a distant queen Who can overween and intervene Can we finally make her obsolete?