full circle

• (UK) IPA^(key): /ˌfʊl ˈsɜː.kəl/
• (UK) IPA^(key): /ˌfʊl ˈsɝ.kəl/

• Audio (General Australian):

  (file)

full circle (plural full circles)

1. Used other than figuratively or idiomatically: see full,‎ circle.
2. (geometry) An arc of 360 degrees.
   • 2007, Carolyn C. Wheater, Geometry, page 193:

     Arcs are measured in degrees, with 360° in the full circle.

3. A full turn back to the original direction or orientation. a point arrived at which is the same point at which it began;
   • 2006, Jack Dawson, Reflections in a Curved Glass, page 31:

     He cackled confidentially, like he knew more than he was telling, then threw his head back and crowed once and strutted in a full circle like a rumpled old rooster.

   1. By extension, when a debate or discussion comes "full circle" when the participants end up going over points already discussed, even though no literal change of orientation is involved. the point at which effort has resulted in no progress.
4. (Can we verify⁽⁺⁾ this sense?) (Taixuanjing tetragram) 𝌇

   U+1D307, 𝌇 UNICODE TETRAGRAM FOR FULL CIRCLE

In geometry, a full circle is properly an arc of 360°, but informally it may be used to refer to the angle measure subtending that arc.

• (geometry): perigon
• (full turn): revolution, rotation

full circle (not comparable)

1. Through a rotation or revolution that ends at the starting point.
   • 1983, Dorothy Koster Washburn, Structure and Cognition in Art, page 138:

     Thus, patterns whose parts move about a point axis are called finite, because eventually the parts will move full circle to superimpose upon the original starting point […]

   • 2020 August 26, Andrew Mourant, “Reinforced against future flooding”, in Rail, page 58:

     Little has been heard lately of Gwynedd Council's campaign for the line to be upgraded for freight use, enabling it to haul slate waste from Blaenau Ffestiniog for export to Europe. [...] It would mean things have gone full circle, for the line's original purpose was transporting slate from Ffestiniog quarries to a quay at Deganwy for shipping abroad.

2. (idiomatic) Through a cycle of transition, returning to where one started after gaining experience or exploring other things.
   • 1963 August, “New 5,000 H.P.-Plus Diesels for U.S. Railroads”, in Modern Railways, page 127:

     Now the wheel is turning back full circle.

   • 2001, Peter M. Coan, Taxi: The Harry Chapin Story, page 139:

     He'd begin with a premise and wrap it up at the end, full circle, the moral of the story hanging on the last word of the last line.

   • 2012, John Schuster, Descartes-Agonistes: Physcio-mathematics, Method & Corpuscular Mechanism 1618-33, page 213:

     This therefore marks our return full circle to the optical proofs in the Diotprique with which our detective work began.

• come full circle

• square the circle

• “full circle”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.