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an abbreviation for Future-sister-in-law.
Jenn and I are FSILs for life, becuase I am marrying Nick Jonas and she is marrying Joe Jonas.
by Me =) April 10, 2008
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Sep 9 Word of the Day
the thing that you don’t have when you’re phones percentage is over 20
phone: why don’t you go to sleep tommy it’s 2 in the morning?
tommy:why don’t you die you dumbazz
by lik_frls_dis.me February 12, 2020
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