bob and shingle?

[Eway]

About hairstyle fashion in 1920s: "Hair was bobbed or shingled."

My dictionary gives "bob" and "shingle" the same definition, i.e. cut short. So are they just the same idea?

[Ouisch]

The bob and the shingle are similar; both are short, blunt cuts. But the shingle is cut shorter in the back and leaves the hair on the sides longer, while the bob is uniform in length on the sides and in the back.

[Humble]

Hi,
I wonder what they call the style (or should I say hairdo?) so loved by many middle-aged and older women when the hair is approximately on the chin level, not reaching the shoulders? I thought it was the shingle. Another question:
Once I saw in the New Yorker sth like "The women were well-coiffed..." I know it's from French (coiffure), but how common is it?
Tnx