The study of the tracks left behind as words and meanings develop and evolve. Sometimes, this can lead to interesting perspectives that can loosen assumptions, expecially when applied to words of common usage. For example, when we say that something "exists" we often mean that something is solid and certain. But the roots of the Latin "exsistere" are "ex" ("out") and "sistere" which means "to stand up". So what we are saying can also simply means that there is a "standing out", a "vividness".