1 [in singular] the period between childhood and adult age:he had been a keen sportsman in his youth
[mass noun] the qualities of vigour, freshness, or immaturity as associated with being young:she imagined her youth and beauty fading
an early stage in the development of something:this publishing sector is no longer in its youth
2a young man:he was attacked by a gang of youths
[treated as singular or plural] young people considered as a group:black youth has experienced high levels of racial discrimination [as modifier]:youth culture