Adolescence (from Latin adolescere, meaning "to grow up")[1] is a transitional stage of physical and psychological human development that generally occurs during the period from puberty to legal adulthood (age of majority).[1][2][3] The period of adolescence is most closely associated with the teenage years,[3][4][5][6] though its physical, psychological and cultural expressions may begin earlier and end later. For example, although puberty has been historically associated with the onset of adolescent development,[7][8][9] it now typically begins prior to the teenage years and there has been a normative shift of it occurring in preadolescence, particularly in females (see precocious puberty).[4][10][11] Physical growth, as distinct from puberty (particularly in males), and cognitive development generally seen in adolescence, can also extend into the early twenties. Thus chronological age provides only a rough marker of adolescence, and scholars have found it difficult to agree upon a precise definition of adolescence.