adolescence (n.) Look up adolescence at Dictionary.com
"age following childhood, age of growing" (roughly the period from the 15th to the 21st year; or age 14 to 25 in males, 12 to 21 in females), early 15c., from Old French adolescence (13c.), from Latin adolescentia/adulescentia "youth, youthful people collectively," abstract noun from adulescentem "growing, youthful" (see adolescent (n.)). Adolescency (late 14c.) is slightly earlier.