Definition of catheter in US English:



  • A flexible tube inserted through a narrow opening into a body cavity, particularly the bladder, for removing fluid.

    • ‘One of the main sources of nosocomial bloodstream infections is intravascular catheters.’
    • ‘This will involve placing a small rubber tube called a catheter in the abscess to drain out the fluid.’
    • ‘Patients should also have a nasogastric tube and urinary catheter inserted.’
    • ‘This relieves the obstruction to the flow of urine by passing a urinary catheter to empty the bladder.’
    • ‘It is often helpful to insert a urinary catheter, so that the diarrhoea can be accurately quantified by recording the stool weight.’


Early 17th century: from late Latin, from Greek kathetēr, from kathienai ‘send or let down’.