Adjective at work has 2 senses
  1. at work - on the job; "had been at work for over an hour before her boss arrived"
    Antonym:
    idle (indirect, via busy)
  2. at work, operant - having influence or producing an effect; "many emotional determinants at work"; "an operant conscience"
    Antonym: inoperative (indirect, via operative)
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