An exceedingly cute way of saying thanks, as used between lovers or when the speaker wishes to imply an element of childish gratitude

*hands the gf the remote*
he: "here you are my darlink!"
she: "fankoo" *smiles*
*bystander rolls eyes and shakes head, grinning*
by Sassielassie September 10, 2006
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Devolution of 'Thank-you'.
Some dude: coos i haves some ends?

Guy: Okay *hands over some money*


some dude: fankoo
by Gumba Gumba February 25, 2004
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