hairy cell leukemia a form of chronic leukemia marked by splenomegaly and by an abundance of abnormal large mononuclear cells covered by hairlike villi (hairy cells) in the bone marrow, spleen, liver, and peripheral blood.
A set of orbitals are said to be degenerate if they all have the same energy. This degeneracy can sometimes be lifted by external electric or magnetic fields.
Metallic hydrogen is a state of hydrogen which results when it is sufficiently compressed and undergoes a phase transition (from one phase or state of matter to another); it is an illustration of degenerate matter (degenerate matter is matter which has such extraordinarily high density).