lostainic Posted in L Best definition lostainic Adjective. Slang for ‘local, sustainable, and organic’. Describes something, (particularly food), that fits all three aforementioned criteria. The restaurant offered lostainic produce from the local farmer’s market. How satisfied are you with the definition? Looking for lostainic meaning? Delighted that you discovered the greatest determine on our web site! Recently this definition was actually observed 43 times.