Definition of isthmus in English:


Pronunciation: /ˈɪsθməs//ˈɪsməs//ˈɪstməs/


  • 1A narrow strip of land with sea on either side, forming a link between two larger areas of land.

    • ‘The best way to cross the isthmus by land is to ride the historic Panama Canal Railway from Panama City to Colon.’
    • ‘Behind him was a narrow isthmus leading to Charlestown, and before him was his goal: the besieged city of Boston.’
    • ‘In the south-east a narrow isthmus enlarges to a knot of salt ponds.’
    • ‘It had once been an island city, but Alexander the Great had conquered it by building an isthmus from the mainland out to the island.’
    • ‘Only one study to date has used calibration points from the fossil record to estimate the divergence of sister species distributed on both sides of the isthmus.’
    • ‘After the Darien experience, participatory mapping initiatives took root during the 1990s along the Central American isthmus.’
    • ‘The isthmus of Land's End was supposedly once connected to the Scilly Isles.’
    • ‘Land routes are really old, especially through isthmuses.’
    • ‘At 20 miles long and four to eight miles wide, the isthmus connects central Greece with the Peloponnese peninsula.’
    • ‘The method diffused rapidly and initiatives developed up and down the Central American isthmus during the 1990s.’
    • ‘He goes over to where Paterson had started to direct construction of a great highway over the isthmus to the Pacific Ocean.’
    • ‘The southern region is a narrow isthmus with hills running down the center.’
    • ‘The town in on the west side; on the north a narrow isthmus (neutral ground) connects the fortress with the mainland of Spain.’
    • ‘The green is cleverly set into a tiny isthmus so that water surrounds three sides.’
    • ‘Currently, the narrow isthmus of southern Armenia, which is squeezed from both sides by Azerbaijan has been officially considered a ‘borderline territory.’’
    • ‘It is joined to the main island by a narrow isthmus.’
    • ‘The toll for crossing the isthmus could easily be a week's salary for a campesino.’
    • ‘The British arrived almost a century ago to build the railroad that slices across the isthmus, linking the Gulf of Mexico to the Pacific Ocean.’
    • ‘The narrow isthmus, heavily defended by the Turks, was their battlefield for the next eight months.’
  • 2Anatomy
    A narrow organ, passage, or piece of tissue connecting two larger parts.

    • ‘Thoracic aortic injuries most often occur at the aortic isthmus in the majority of the cases.’
    • ‘The adult gland weighs 10-20 g and consists of two relatively flat oval lobes linked by an isthmus.’
    • ‘The cervix forms the lower third, connected by a narrow isthmus to the main muscular body of the uterus.’
    • ‘It is usually attached to the isthmus on the left side of the median plane, but it may join either of the lateral lobes.’
    • ‘It has 2 lobes, called the right lobe and the left lobe, joined by a narrow isthmus.’


Mid 16th century: via Latin from Greek isthmos.