Definition of thenar in US English:



  • Relating to the rounded fleshy part of the hand at the base of the thumb (the ball of the thumb).

    • ‘Shaking the patient's hand at the end of the consultation, the doctor noticed a raised lesion on the thenar eminence of his right hand.’
    • ‘Although it is uncommon, swelling in the thenar or midpalmar spaces of the hand suggests an infectious etiology.’
    • ‘Decreased grip strength may result in loss of dexterity, and thenar muscle atrophy may develop if the syndrome is severe.’
    • ‘Wasting of the thenar muscle occurs in under 10% of cases.’
    • ‘The nerve also supplies a branch to the muscles of the thumb, the thenar muscles.’


Mid 17th century: from Greek, literally ‘palm of the hand, sole of the foot’.