The time of life when one is expected to take responsibility for one's own actions and well-being.(noun)
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Use "adulthood" in a sentence
"I can only hope that whatever they choose to do in adulthood is because they chose to do it."
"The most important thing is not to infect the child with what you call "adulthood.""
"If the subset of students most likely to continue problem drinking in adulthood can be identified during college, they might benefit from counseling or programming that specifically aims to lower long-term high-risk drinking, the researchers say."