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ballflower

American  
[bawl-flou-er] / ˈbɔlˌflaʊ ər /

noun

Architecture.
  1. a medieval English ornament suggesting a flower of three or four petals enclosing and partly concealing a ball.


ballflower British  
/ ˈbɔːlˌflaʊə /

noun

  1. architect a carved ornament in the form of a ball enclosed by the three petals of a circular flower

"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

Etymology

Origin of ballflower

First recorded in 1835–45; ball 1 + flower