noun

• 1A device for retracting something.

  ‘seat belts with automatic retractors’

  More example sentences

  • ‘Easily visualizing the acetabulum, the surgeon places retractors, avoiding sciatic nerve injury.’
  • ‘The surgeon and assistant protect the sciatic nerve with retractors while dividing the hip capsule, leaving all possible structures intact.’
  • ‘The surgeon places two self-retaining retractors at right angles to one another to retract the longus colli muscles.’
  • ‘The surgeon makes the skin incision and places a self-retaining retractor to open the surgical wound.’
  • ‘Operating times were measured starting from the placement of the lid retractors to their removal at the end of the procedure.’

  1. 1.1Zoology A muscle serving to retract a part of the body.
     Compare with protractor
     ‘The literature on echinoderm neurobiology is sparse, but one of the few studies available found that the pharyngeal retractor muscle of the holothurian Cucumaria has perhaps 700 motor units.’
     More example sentences

     • ‘On the day of the experiment, the shell was opened, the anterior byssus retractor muscle was exposed, and the pedal ganglia removed.’
     • ‘In the overhead thrower, the shoulder external rotator muscles, scapular retractor muscles, and protractor and depressor muscles are frequently isolated because of weakness.’
     • ‘It is tempting to hypothesize that because the limb girdles display positive allometry, the protractor and retractor muscles attached to them did as well.’
     • ‘Although all of the protractor and retractor muscles have roles in swing phase, most play little or no role in support phase when dogs trot at steady speed on the level.’