surreptitious

/ˌsɜrəpˈtɪʃəs/
adjective
  1. Done in a secret or stealthy way to avoid being noticed.
    • He took a surreptitious glance at his phone during the exam.
    • They exchanged surreptitious smiles across the crowded room.
    • The cat made a surreptitious move toward the bird feeder.
Antonyms
What does "surreptitious" mean? | whatsthatwordmean | whatsthatwordmean