MAHRAM - محرم
Literally: Prohibited. A forbidden place for certain acts; a sacred place.
As a Sharî’ah term: Used especially, within the forbidden degrees of relationship for marriage; as such of different sexes, may meet on intimate terms. Intimate.
A mahram is an unmarriageable kin with whom marriage or sexual intercourse would be considered haram.
Mahrams of a woman:
Her father, her father-in-law, her son, her husband’s son from his previous wife, her grandfather, her brother, her nephews, her grand-nephews, her paternal and maternal uncle, her milk brother, her mothers and fathers uncles (paternal and maternal).
Mahrams of a man:
His mother, his daughter, his sister, his paternal and maternal aunt, his grandmother, his nieces, his grand-nieces, his milk mother, his milk sister, his mother-in-law, his wife’s daughter from her previous husband, his son’s wife, his mothers and fathers aunts (paternal and maternal).