(biology) The course of stages through which an organism passes from fertilized zygote until maturity, reproduction, and death.

plural of fact of life / (euphemistic) knowledge of sexual reproduction (almost always used with the)

Something that cannot be avoided.

(idiomatic, chiefly UK and Ireland) The real world as a source of instruction, as opposed to a formal education.

The morphology of an organism that distinguishes it from others. / Alternative form of lifeform

(Hinduism, Buddhism and Jainism) A mandala, representing the continuous cycle of birth, life and death.

Immortality. / (religion) Life after death; the afterlife.

(idiomatic) Absolutely not; under no circumstances.

Any large portion of the Earth's land area which has a generally uniform climate and soil and therefore a high degree of uniformity in the composition of species; a number of different classifications have been proposed by different people.

Full-scale, as a model that is the same size as what it is a model of.