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planform

American  
[plan-fawrm] / ˈplænˌfɔrm /

noun

  1. the outline of an object viewed from above.


planform British  
/ ˈplænˌfɔːm /

noun

  1. the outline or silhouette of an object, esp an aircraft, as seen from above

"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 planform

First recorded in 1905–10; plan + form