They think going to clubs, excessive drinking, sleeping around or explicit relations means maturity.
While some of those things are perks to being an adult, what really makes someone mature is growing past that sort of way of life mentally. Taking responsibility and using discernment when making serious (and possibly life altering) decisions. Or as the dictionary describes it…
Mature
adjective
adjective: *mature
having reached an advanced stage of mental or emotional development characteristic of an adult.
comparative adjective: maturer ; superlative adjective: maturest
“a young man mature beyond his years”
Similar:
sensible
responsible
adult
Being mature isn’t just a physical thing, it’s a mental thing as well.