Acronym for flakey idaho person. One who resides in the state of idaho and who more often than not flakes out when they promise to be somewhere or do something
Rose: Hey where is Rio i thought she said she was coming?
Franklin: Nah, she's being a FIP.
Rose: This is the third time Sara has asked to meet somewhere and then stood me up!
Understanding Friend: Oh, but this is idaho, right? She's just being a fip.