getting annoyed easily; showing your anger synonym bad-tempered to be tired and irritable an irritable gesture Word Origin mid 17th cent.: from Latin irritabilis, from the verb irritare.Extra examples Don’t let yourself become irritable with the patient. Having the children at home made him irritable. He got quite irritable with us. He sounded rather irritable on the phone. She was feeling extremely irritable that morning. He was tired and irritable. She waved him away with an irritable gesture.