The successive stages through which an organism passes from fertilized ovum or spore to the fertilized ovum or spore of the next generation.
The artificial segments of the life span. Each segment represents a developmental period: birth, maturity, aging, and dying.
All of the developmental history of an organism, whether in a free living condition or in a host (e.g., as a parasite that experiences part of its cycle inside another organism).
The process of developmental phases that an organism undergoes, starting from its inception, progressing through maturation, reproduction, and ultimately culminating in death. This concept is commonly applied to animals that undergo distinct transformations during different life stages, such as insects and worms.