Definition of apothem in English:

apothem

noun

Geometry
  • A line from the center of a regular polygon at right angles to any of its sides.

    • ‘Given a circle, the apothem is the perpendicular distance from the midpoint of a chord to the circle's center.’
    • ‘For a polygon of n sides, there are n possible apothems, all the same length of course.’
    • ‘We can find the apothem from the side length and the number of sides.’
    • ‘Once the perimeter and the apothem are known, the formula relating the two to area can be used to solve for the area.’
    • ‘In a regular polygon, we have an apothem, a number and a length of sides which do not belong to the base class shape.’

Origin

Late 19th century: from Greek apotithenai put aside, deposit from apo away + tithenai to place.

Pronunciation:

apothem

/ˈapəˌTHem/