The age at which a person is first capable of sexual reproduction.
The process of sexual development that produces secondary sex characteristics and makes a person capable of reproducing sexually.
The period when a plant begins to flower.
A developmental phase brought about by the action of hormones as part of the maturing process. For humans, there are three in total.
The time of life between thirteen and nineteen years old; the teenage years.
The second decade of a century: the 1910s, 2010s, etc. The oneties, the tens.
The numbers between thirteen and nineteen.
The range between 10 and 19.