"Fags out" is an informal phrase that typically means to tire out, exhaust or lose energy. Some of the antonyms for "fags out" include resuscitate, energize, invigorate, refresh and rejuvenate. These words imply a sense of restoring or regaining energy, rather than losing it. Other antonyms for "fags out" include motivate, stimulate, encourage, inspire and activate. These words imply a sense of being moved to action or excitement, rather than experiencing a lack of energy. In summary, the antonyms for "fags out" express ideas of renewal and activation, as opposed to lethargy and exhaustion.