Age

(aj). The length of time a being has existed; also, a certain stage in life. The period of life is divided into a succe ion of ages, as follows: I. Infancy, from birth to the appearance of the temporary teeth. 2. Childhood, from the cutting of the first permanent teeth to puberty. 3. Youth, from puberty to the attainment of the full stature, that is, 18 or 19 for girls, 21 to 22 for boys. 4. Maturity, covers the interval from youth to the climacteric. 5. Old-age, or period of decline. Other divisions may be made, as, e. g., those of embryonic life, of immaturity, of maturity, of sterility, etc. Agenesia (ah-jen-e' -se-ah). A term somewhat loosely used to designate abnormal or imperfect development. Also impotence and sterility. In botany, the asexual development of the flower.