Ethos, a noun, is the fundamental set of beliefs that you, or a society, or group live by. A free spirit might live by the ethos of "anything goes."
The noun ethos refers to how you, or a group, or a society chooses to live and is the particular rules and characteristic values that organize people. This also means that a different group might have a different ethos. An example is that in some cultures the individual is highly valued while in others the group might be considered central. In literary studies ethos has a moral element attached to it but sociology describes ehos.
