irascibly
Definitions
In a manner characterized by a tendency to be easily angered.
With a quick-tempered or irritable disposition.
Examples
The tired professor responded irascibly when the student asked the same question for the third time.
He paced the room irascibly, muttering about the delays that had ruined his carefully planned schedule.
Synonyms
testily crabbily peevishly short-temperedly snappishly crossly petulantly
Antonyms
patiently amiably good-naturedly calmly placidly affably genially