An evolutionary hypothesis which proposes that organisms must constantly adapt, evolve, and proliferate not merely to gain reproductive advantage, but also simply to survive while pitted against other evolving organisms in an ever-changing environment.

(historical, chemistry) An early 19th-century attempt to explain the existence of the various chemical elements: the hypothesis that, since the atomic weights for known elements appeared to be whole multiples of the atomic weight of hydrogen, the hydrogen atom was the only truly fundamental object, and the atoms of other elements were actually groupings of various numbers of hydrogen atoms.

(religion) Baptism administered to somebody who may or may not have been baptized before.

Less than normal activation

(evolutionary theory) The hypothesis, in evolutionary biology, that a female animal's optimal choice among potential mates is a male whose genes will produce male offspring with the best chance of reproductive success, irrespective of the mate's capacity as a caregiver or any other direct benefits he can offer.

The condition of being hypoactive

Relating to, or afflicted with, hypoadrenocorticism.

(pathology) adrenocortical insufficiency; Addison's disease

The hypothesis that the Torah (the first five books of the Bible) was derived from originally independent, parallel, and complete narratives, which were subsequently combined into the current form by a series of redactors.

The hypothesis that God exists, seen as something able to be analyzed by a scientific approach rather than accepted by faith.