What is Sibling?
1.
One's exact opposite, created by someone's parents to torture him/her until death.
Sibling rivalry is common among siblings.
2.
A younger brother or sister.
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3.
A child born of your mother's womb who is used as a unit of comparison in the family.
Mom: (Chiding) "Your brother sent me flowers for my birthday. Why can't you be more like him?"
Steve: "Ah, Mom! Can I help it if my sibling has more money to waste than me?"
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4.
A combination of a best friend and a punching bag
Tony is my sibling. He bugs the heck out of me, but I love him so much.
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5.
A brother or sister.
A being with whom you share parents, whose sole purpose is to destroy your life.
In general, younger siblings are slightly more annoying than older ones, although in general older siblings are meaner and stronger so beat up the younger one.
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6.
From the infinitive 'to sible' (pronounced 'sibble'), meaning to perform some form of sexual act with another persons brother or sister (preferably younger for greater novelty value...though not TOO much younger). For clarity in use, the given example would mean that to sible 'her', would be to sleep with 'her' sibling.
'Dude, I would totally sible her...soon as her younger sister's street legal of course.'
'For sure dude! I'd give her the sibling of a lifetime.'
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