Stands for:

I
Feed
Naughty
Nutcrackers
During
X-mas

The act of luring mischievous nutcrackers under mistletoe with food, in order to get a nice woody kiss.
Guy 1: Dude did you just see what Josephine did?
Guy 2: No, what happened??
Guy 1: She totally just ifnndx'ed that weird living nutcracker guy!
Guy 2: No way! I wonder what it's like to kiss a literal block of wood...
by CMell December 5, 2019
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