Definition of tibia in US English:



  • 1The inner and typically larger of the two bones between the knee and the ankle (or the equivalent joints in other terrestrial vertebrates), parallel with the fibula.

    • ‘X-rays later revealed that both the tibia and fibula bones in Marcus's right leg fractured.’
    • ‘The earliest members of the group had two separate leg bones, the tibia and fibula, just like humans.’
    • ‘The kneecap is then moved across to the outer side of the knee to expose the knee joint behind it, between the tibia (shin bone) and the femur (thigh bone).’
    • ‘However, as a 4 year old he had a fractured tibia and fibula.’
    1. 1.1Zoology The tibiotarsus of a bird.
      • ‘The left tibia was removed from each bird, cleaned, and marked for identification.’
      • ‘A bird with a broken tibia popped off her own cast after a week.’
      • ‘Severely affected birds may have a marked bowing of the tibia, be reluctant to move, and have a stilted gait.’
    2. 1.2Entomology The fourth segment of the leg of an insect, between the femur and the tarsus.
      • ‘Both sexes have a pair of ‘spurs’ on each hind leg where the tibia, or fourth leg segment, joins the tarsus, or foot.’


Late Middle English: from Latin, ‘shin bone’.