"Dress is the way in which individuals learn to live in their bodies and feel at home in them" (Entwistle 7).
"Modish" dress is dress which styles continuously change
"Fixed" dress includes traditional religious and ethnic garments and describes dress that is "characterized by its continuity with the past rather than the logic of 'change for change's sake'" (Entiwistle 45).  Fixed is not entirely an accurate term as traditional dress can and does evolve over time, although not at the rapid rate of fashion; more accurately we could term it "quasi-fixed" dress. 
'"Fashion" is a general term which can be used to any kind of systemic changes in social life' (Entwistle 45)
"Fashion is dress in which the key feature is rapid and continual changing of styles: fashion in a sense is change"(E.Wilson as quoted in Entwistle 2000: 45).

Source cited:
Entwistle, Joanne. (2000)  The Fashioned Body: Fashion, Dress, and Modern Society. Malden, MA: Blackwell Publishing, Inc.

Considerations: Dress and demonstrations of power. Does (or how does) dress emphasize and reinforce specific systems of power in western society?  Gender binaries?  Feminism? Socio-economic?