[sem-i-sur-kuh l]


Also called sem·i·cir·cum·fer·ence [sem-ee-ser-kuhm-fer-uh ns, -fruh ns, sem-ahy-] /ˌsɛm i sərˈkʌm fər əns, -frəns, ˌsɛm aɪ-/. half of a circle; the arc from one end of a diameter to the other.
anything having or arranged in the form of a half of a circle.

Origin of semicircle

From the Latin word sēmicirculus, dating back to 1520–30. See semi-, circle
Related formssem·i·cir·cu·lar [sem-i-sur-kyuh-ler] /ˌsɛm ɪˈsɜr kyə lər/, adjectivesem·i·cir·cu·lar·ly, adverbsem·i·cir·cu·lar·ness, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for semicircle

arc, hemicycle

Examples from the Web for semicircle

Contemporary Examples of semicircle

Historical Examples of semicircle

  • Outside the wide doors of the corridor the wheel-chairs were arranged in a semicircle.


    Mary Roberts Rinehart

  • Seated on the ground, in a semicircle, were half a dozen dejected prisoners.

  • He reached a chair placed in the focus of the gathering, which sat in a semicircle.

  • They stood in the middle of the semicircle, immediately facing the bishop.

    Victor's Triumph

    Mrs. E. D. E. N. Southworth

  • The latter is laid out in a semicircle, and is crowned by cupolas and minarets.

    Hampstead and Marylebone

    Geraldine Edith Mitton

British Dictionary definitions for semicircle



  1. one half of a circle
  2. half the circumference of a circle
anything having the shape or form of half a circle
Derived Formssemicircular (ˌsɛmɪˈsɜːkjʊlə), adjectivesemicircularly, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for semicircle

1520s, from semi- + circle (n.) or else from Latin semicirculus.

Online Etymology Dictionary, © 2010 Douglas Harper