junior

Concise Oxford English Dictionary © 2008 Oxford University Press:
junior/ˈʤuːniə(r)/

▶adjective

• 1 for or denoting young or younger people.

  ■ Brit. for or denoting schoolchildren aged 7–11.

  ■ N. Amer. of or for students in the third year of a four-year course at college or high school.

• 2 [postpos.] denoting the younger of two with the same name in a family.

• 3 low or lower in rank or status.

▶noun

• 1 a person who is a specified amount younger than someone else: he's five years her junior.

• 2 Brit. a child at a junior school.

  ■ N. Amer. a student in the third year at college or high school.

  ■ (in sport) a young competitor, typically under 16 or 18.

  ■ N. Amer. informal a nickname for one's young son.

• 3 a person of low rank or status.

– derivatives
juniority /-ˈɒrɪti/ noun.

– origin ME: from L., compar. of juvenis ‘young’.