"Spontaneous" refers to actions or events that occur without premeditation or planning. It often describes behaviors that are impulsive or natural, arising from internal feelings rather than external constraints. For example, a spontaneous decision to go on a trip can lead to unexpected adventures and experiences. In biology, "spontaneous" can describe processes that happen naturally without external influence, such as spontaneous generation, which is the idea that living organisms can arise from non-living matter. This concept has been largely discredited, but it highlights the idea of natural occurrences in various fields, including chemistry and physics.