Millitary Acronym for Lost Like a Mother Fucker. Usually spelled out using the millitary phoenetic alphabet.
Officer: "Uhhh...anyone know where we are?"
Sergeant: "Man, we are Lima Lima Mike Foxtrot!"
laughing like a mother fucker
Sofia:(telling a funny joke)
Emily:Im LLMF at this!!!!!!
Sofia: What does that mean
Emily it mean that I'm laughing like a mother fucker