Definition of letter opener in US English:

letter opener

noun

  • A tool used for opening envelopes, typically one shaped like a knife.

    ‘a letter opener can be seen at the front of the desk’
    • ‘She slit the side of the thick envelope with the tarnished letter opener.’
    • ‘He pulled the plastic bag containing the letter opener out of his jacket pocket.’
    • ‘Maybe the he couldn't find money in the budget for a letter opener.’
    • ‘Police now believe the letter opener to have been the murder weapon.’
    • ‘I've had one letter opener seized, and two Swiss army knives.’