n.
Pronunciation: ˌ ir- ə -t ə - ' bi-l ə -t ē
Function: noun
Inflected Form: plural -ties
Date: 1755
1 : the property of protoplasm and of living organisms that permits them to react to stimuli
2 : the quality or state of being irritable: as a : quick excitability to annoyance, impatience, or anger : PETULANCE b : abnormal or excessive excitability of an organ or part of the body