Continuous comes from the Latin continuus which is a form of continere meaning to hold together. It may have different meanings, including moving through time, or substance without interruption, or attached in repeating units. Constant, on the other hand, refers either to something recurring regularly or unchanging or invariable. In these senses, these words are adjectives. Constant can occur as a noun, too. In this case, it refers to a factor that is permanent or invariable. In algebra, it relates to a quantity that remains at a fixed value throughout a given discussion. In science, it means any property in an experiment determined numerically which does not change under particular circumstances. Finally, in computing, it refers to an identifier that is bound to an invariant value.
