Most Orthodox Jewish women cover their hair in some way. Whether they cover most or all of it, and what type of covering they use, is a matter of which rabbinic ruling they follow, family/community custom, and personal preference. A wig is considered a full covering according to most opinions, since it isn't the woman's own hair. It used to be obvious that a wig was being worn, but since wigs have gotten so lifelike, some prefer not to wear them, or to wear them with a hat or scarf on top. In some communities a scarf is worn with a small hairpiece of hair or silk threads (to look even less like hair) in the front- a higher level of observance being to wear only a scarf. Other opinions say that a wig is better as it is easier to conceal all the hair. Some women cheat, though, and tease some hair out in front for a more natural hairline! I feel that a scarf covering all the hair is honest and promotes a more spiritual feeling.
If you think all that's complicated, just ask about Orthodox men's hat styles!
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Laughing and calling her name, they splashed into the foaming water and swam with her until the break of day.
The trouble with being an etymologist is that people keep bringing you bugs to look at.