The quality or state of being fretful; persistent worry, irritability, or restlessness.
From 'fretful' plus '-ness' (suffix forming abstract nouns from adjectives). This represents the abstract noun formation pattern in English, creating a noun that names the quality itself rather than a person or instance.
The '-ness' suffix is one of English's most productive tools for making abstract qualities—fretfulness, kindness, sadness all follow this same pattern, letting us talk about emotional states as tangible properties!
Complete word intelligence in one call. Free tier — 50 lookups/day.