Lowlifes are often defined as people who engage in criminal or immoral activities. If you're looking for alternative words to describe these individuals, there are plenty of synonyms available. Some options include delinquents, miscreants, scoundrels, rascals, and ne'er-do-wells. Other potential synonyms might include rogues, reprobates, scum, scumbags, or even troublemakers. Still, others might use terms like hoodlums, hooligans, criminals, or villains. Ultimately, the choice of synonym will depend on the tone and context of your writing or conversation, but any of these words can be an effective substitute for "lowlifes".