The word ‘Blouse’ comes from French, and means ‘dust coat’. As with many words the meaning, use and denoted object have changed over time. Where the blouse garment was once a loose fitting garment worn by workmen and peasants, often made of cheap material and favoured for its cheapness and convenient ease-of-movement, it is now a more stylish garment worn almost exclusively by women. The blouse is still loose fitting, and gathered more tightly at the waste; otherwise there is little in common between modern fashionable blouses and older pleasant clothing.
The differences between a women’s shirt and a blouse consist of many minor details, but the lack of a collar on a blouse is one important distinction. Blouses also tend to feature more frills and pleats, and tend not to have any practical pockets. Some blouses are made to be buttoned up from the back; but as with women’s shirts they follow the tradition of reversing the direction of buttons in respect to men’s clothing.
Fashion has not reached an end. Blouses will change and elements in the design of blouses will influence other clothing items. A Blouson (sometimes called a blouse jacket) takes the loose fitting idea of a blouse and adds the pockets from a shirt to the material and function of a jacket. Other variations and combinations will doubtlessly develop over time.
As a blouse is designed to be loose fitting there is little danger of ordering one in the wrong size; there is a fair margin for error. As long as an individual knows the approximate size that can order anything that suits their sense of style.