is like a river
It flows through time from its earliest sources, picking up new meanings at each confluence.
Culture, the collective experience of those who speak it, is the lay of the land in which speakers speak.
The streams flowing into the great tributaries of living language are the lived lives of the individuals who actually speak. They are free to say anything that they can, but can only say what they can.
Living language, once spoken, is an artifact. But for a second, just, it is alive with all the hopes, all the fears, all the thwarted expectations of every speaker.
Etymology is the study of these rivers.