FAQ

In this case, T.L. stands for "two-liner", which is when someone tells the first part of something followed by the second part. In this instance, Jeff tells Orville that they didn't just flip the coin for food. He then says it was to determine who eats who. Hope & Crosby tended to use that phrase in various movies.

Another interpretation is that it stands for "trade-last". A favorable remark that one has overheard about another person and offers to repeat to that person in exchange for a compliment overheard about oneself.