Definition of shoulder surfer in US English:

shoulder surfer

noun

informal
  • See shoulder surfing

    • ‘Shoulder surfers use similar tactics to those used with ATMS when tourists make credit card calls on public phones.’
    • ‘Once they've captured your PIN, the shoulder surfers will try to steal your wallet or purse so they can get your ATM card.’
    • ‘Beware of shoulder surfers when you go to the ATM.’
    • ‘Be on the lookout for "shoulder surfers" when using automated teller machines.’