look up any word, like donkey punch:
 
1.
sister-in-law; this is a way to refer to your SIL without having to call her 'sister'.

While in written communications one can use 'SIL', in spoken communication using the term 'silster' is both more descriptive and specific than saying 'sister-in-law'. And it's more concise as well, offering a savings of 50% (two syllables instead of four for 'sister-in-law'!

'Silster' is a useful term for those having trouble accepting the wife of their brother or the female sibling of their husband. It has a certain mouth-feel which reveals this reluctance and difficulty.
Somehow I survived a long weekend with my silster at the parents' place.
by skwerlgirl August 20, 2009