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Yagi aerial

British  
/ ˈjæɡɪ, ˈjɑːɡɪ /

noun

  1. a highly directional aerial, used esp in television and radio astronomy, consisting of three or more elements lying parallel to each other, the principal direction of radiation being along the line of the centres

"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 Yagi aerial

C20: named after Hidetsugu Yagi (1886–1976), Japanese engineer