(countable, uncountable, immunology) A glycoprotein found on the surface of helper T cells and several other types of immune cells. / (countable, immunology) A CD4+ helper T cell.

Our universe, the sum of everything that exists in the cosmos, including time and space itself.

(intransitive) To flourish.

(biology) A structure (half of a desmosome) on the basal surface of some cells