Tuna Lip Share definition Flag A lesbian and or bisexual woman that may hide the fact that she likes women. 1. "I have a feeling that Rachel is a Tuna Lip." 2. "I think Rorie and The Pirate might be Tuna Lips!" Tuna Lip by 49 Cayman January 11, 2009 0 0 Get merch Get the Tuna Lip mug. Buy Now — $32.95 See more merch