lanugo: the calculated unit of time between the beginning of a Bill Cosby impersonation and the point where the impersonator makes a Jello Pudding reference (Will)

latrobe: the last effort of an ailing country to stay underwater for just a few more seconds (Bryan)

liebig (1): nationality-changing paintballs. "Haha, you're Croatian!" (Mitch)

liebig (2): the "Devil Went Down to Georgia" action figure set (Corey)

logie: the first word to mean 'logic', but it didn't make sense, so they changed it (Mark)

loppet: to stumble, while walking or running, into a vat of ill-tempered wolverines with ADD, so they forget to hurt you and you can just swim through (Bryan)

lusk : a Mormon fish tickler (Derek)