mahram

In Islamic sharia legal terminology, a mahram (Arabic محرم, also transliterated mahrim or maharem) is an unmarriageable kin with whom sexual intercourse would be considered incestuous, a punishable taboo. Current usage of the term covers a wider range of people and mostly deals with the dress code practice of hijab.
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One who falls within the prohibited degree for marriage.
One's immediate relatives - according to a certain classification detailed in Shari'a law.
Example: One's mother, sister, aunt,uncle,etc.