Lequaint
To be overly fond of your own voice and always convinced that you are correct, even in the face of overwhelmingly conflicting evidence.
Simon is usually very lequaint.
Simon was being particularly lequaintant today, insisting that all shop bought eggs would hatch if they were incubated.
Simon was being particularly lequaintant today, insisting that all shop bought eggs would hatch if they were incubated.