The possession of adult qualities such as emotional maturity or responsibility.
'Can the degree or quality of an individual's adultness be assessed?'
'When Rock Hudson and Doris Day shared fume and frustration in their prolonged comedic foreplay, there was a hint of adultness about it.'
'The depth and adultness of Connie, however, may well be more due to the stunning performance of Diane Lane than to the script or to Lyne's direction.'
