automatic direction finder

noun

: a navigational tool that continuously displays the bearing of a designated reference radio beacon

But unlike some other relics, the ADF (automatic direction-finder) keeps rearing its ugly head like an uninvited relative who shows up at the family picnic. Instrument pilots who try to fly without a good foundation in ADF needlework can quickly run smack into an indigestible hash of headings and bearings.

—Thomas H. Block, Plane & Pilot, January 1994

—abbreviation ADF

Word History

First Known Use

1938, in the meaning defined above

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