2 adult
Function:
adjective always used before a noun except in sense 2Meaning:
1 : fully grown and developed ▪ an adult student/learner ▪ adult birds ▪ I've worked here all of my adult life. [=I've worked here since I became an adult] ▪ preparing children for adult life
2 [more adult; most adult] : mature and sensible : not childish ▪ We need to approach this in an adult way. ▪ an adult decision/choice/responsibility
3 : of or intended for adults ▪ adult literacy ▪ adult learning
4 : dealing with sexual material ▪ adult bookstores/movies
2 [more adult; most adult] : mature and sensible : not childish ▪ We need to approach this in an adult way. ▪ an adult decision/choice/responsibility
3 : of or intended for adults ▪ adult literacy ▪ adult learning
4 : dealing with sexual material ▪ adult bookstores/movies
—adult·hood 
/əˈdʌltˌhʊd/ noun plural adult·hoods [noncount] ▪ preparing children for adulthood [count] ▪ preparing children for their adulthoods
/əˈdʌltˌhʊd/ noun plural adult·hoods [noncount] ▪ preparing children for adulthood [count] ▪ preparing children for their adulthoods