Was heißt constant? Was heißt constant? Continually occurring; persistent.Regularly recurring: plagued by constant interruptions. Unchanging in nature, value, or extent; invariable. See Synonyms at continual.Steadfast in purpose, loyalty, or affection; faithful. See Synonyms at faithful.Something that is unchanging or invariable.A quantity assumed to have a fixed value in a specified mathematical context.An experimental or theoretical condition, factor, or quantity that does not vary or that is regarded as invariant in specified circumstances.