An expression of depression, or release of a sigh using vocabulary instead of a deflating exhalation. The sauce makes it plural with the "s" sound, and causes ppl to ask wtf is going on. Also an attempted "lol", when in reality something just failed. See also: fml.
"I pooped in my pants...sighsauce."

"I won $1 with my $3 scratchcard. Sighsauce..."

"KNIFE! Take that bitch! <2 seconds later, marty nade explodes> ... sighsauce..."

by j1n February 20, 2009
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