(1) The process in which life forms arise from similar life forms.
(2) It asserts that living things can only be produced by another living thing, and not by a non-living thing.
It is now a common notion that any living thing can only come from another living thing, and no cellular life has ever been observed to arise from non-living matter. For example, a spider lays eggs that will develop into spiders.
Word origin: from (Greek) bios: life + (Greek) genesis: origin, source.
Related forms: biogenetic (adjective), biogenous (adjective).
Related phrases: Law of Biogenesis.
Compare: abiogenesis, spontaneous generation.