noun, noun which may take the genitive case particle 'no'
automaticity; automatism
Refers to the property of being automatic, self-acting, or involuntary. Used in technical, psychological, and general contexts.
The automaticity of this machine is very high.
A certain automatism can be seen in his behavior.
自動的 is a na-adjective meaning 'automatic' in an adverbial or descriptive sense. 自動性 is the noun form for the concept itself.
Compound of 自動 (automatic) + 性 (nature, property). The exact historical derivation is uncertain, but the word follows a common pattern for forming abstract nouns in modern Japanese.