Sister
A female sibling, first-degree relative, and familial term.
A sister is a female sibling—a woman or girl who shares one or both parents with another person. Her male counterpart is a brother. While the word usually describes a family tie, it can also be used affectionately for non-familial relationships. A full sister is considered a first-degree relative.
The English term *sister* traces back to Old Norse *systir* and further to Proto-Germanic *swestēr*, both carrying the same meaning. Research indicates that sisters tend to show more jealousy toward siblings than brothers do. In certain cultures, sisters are traditionally placed under the protection of male siblings, especially older brothers, against threats like bullies or unwanted sexual advances. Over time, the word *sister* has expanded in casual use to include people claiming kinship, leading some publishers to prefer the phrase *female sibling* to avoid confusion. Men with a twin sister sometimes view her as a female alter ego—what they might have been like with two X chromosomes. A study in Perth, Australia, found that girls with only younger brothers experienced a chastity effect, losing their virginity on average more than a year later than usual, possibly due to pheromones in their brothers' sweat or household chores.
In sororal relationships, older sisters often introduce varied gender roles to younger siblings and tend to form close bonds with them. They are also more likely to play with younger siblings. Younger siblings behave more needily around an older sister and are more tolerant of her bad behavior. Boys with only one older sister tend to display stereotypically masculine traits, and this masculinity increases with more sisters. However, young boys with several sisters tend to be more feminine, though they outgrow this by puberty. Boys with older sisters are less likely to be delinquent or have emotional and behavioral disorders. A younger sister is scolded less often by older siblings than a younger brother is. The most common recreational activity between an older brother and a younger sister is drawing. Some studies link having an older sister to more constructive discussions about safe sex. Research also suggests that men without sisters are more likely to struggle with courtship and romantic relationships.
- definition
- Female sibling
- male counterpart
- Brother
- degree of relation
- First-degree relative (full sister)
- etymology
- From Old Norse systir, from Proto-Germanic *swestēr
- colloquial broadening
- Sometimes used for non-familial relationships
Lore & Background
The English word sister comes from Old Norse systir which itself derives from Proto-Germanic *swestēr, both of which have the same meaning, i.e. sister. Some studies have found that sisters display more traits indicating jealousy around their siblings than their male counterparts, brothers. In some cultures, sisters are afforded a role of being under the protection by male siblings, especially older brothers, from issues ranging from bullies or sexual advances by womanizers. In some quarters, the term sister has gradually broadened its colloquial meaning to include individuals stipulating kinship. In response, in order to avoid equivocation, some publishers prefer the usage of female sibling over sister. Males with a twin sister sometimes view her as their female alter ego, or what they would have been like if they had two X chromosomes. A study in Perth, Australia found that girls having only younger brothers resulted in a chastity effect: losing their virginity on average more than a year later than average. This has been hypothesized as being attributed to the pheromones in their brothers' sweat and household-related errands.
Reader's Guide
The concept of sister is significant as a fundamental familial relationship, defining a female sibling who shares one or both parents with another individual. As a first-degree relative, the sister occupies a key role in kinship structures across cultures. Studies cited in the source article indicate that sisters may display more jealousy than brothers, and that cultural norms sometimes place sisters under the protection of male siblings. The term has also broadened colloquially to include non-familial relationships, leading some publishers to prefer 'female sibling' for clarity. Research on sororal relationships shows that older sisters often give varied gender roles to younger siblings and develop close bonds, while younger sisters are less likely to be scolded than younger brothers. Boys with older sisters are less likely to be delinquent, and men without sisters may be less effective at courtship. A study in Perth linked having only younger brothers to a later age of first sexual intercourse for girls. These findings highlight the sister's role in shaping sibling dynamics, gender development, and social behavior, making the term both a biological and cultural touchstone.
Did You Know?
- A full sister is a first-degree relative.
- Some studies have found that sisters display more traits indicating jealousy around their siblings than brothers.
- Males with a twin sister sometimes view her as their female alter ego.
- A study in Perth, Australia found that girls with only younger brothers lost their virginity on average more than a year later than average.
Frequently Asked Questions
What is a sister in kinship terms?
A sister is a female sibling, defined as a woman or girl who shares at least one parent with another individual. She is the female counterpart to the term brother.
What is the etymology of the word 'sister'?
The word traces back to Old Norse 'systir,' which in turn derives from the Proto-Germanic root '*swestēr.'
What degree of relative is a sister?
A full sister is classified as a first-degree relative, meaning she shares both parents with the person in question.
Can 'sister' be used for someone who is not a blood relative?
Yes. Although the term primarily denotes a familial bond, it is sometimes applied endearingly to describe close non-familial relationships.
How does 'sister' differ from 'brother' in kinship classification?
The two terms are direct male-and-female counterparts describing the same sibling relationship; the only distinction is the gender of the sibling being referenced.
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