The phrase "copping some ze" is slang that means to getting some sleep. Antonyms for this phrase could include staying awake, remaining alert, or being active. Other possible antonyms include being restless, staying up late, or avoiding sleep altogether. Depending on the context, antonyms for "copping some ze" could also include being productive, studying, or undertaking other activities that require wakefulness and concentration. Ultimately, the word choice will depend on the desired meaning and intended usage of the phrase in a given situation.