approacher

Noun

approacher (plural approachers)

1. Someone or something that approaches.
   • The monkeys’ calls warn other animals of approachers.
   • […] houses or other thing standing néere vnto a towne, or fort, are meanes to surprise and approach vnto it, and the approacher not be discouered, or impeached by the defenders.1589, Paul Ive (translator), Instructions for the Warres by Raimond Beccarie de Pavie, Seigneur de Fourquevaux, London: Thomas Man and Toby Cooke, Chapter 5, p. 38
2. An asteroid on a near-Earth trajectory.
   • Extensive upgrades to the Arecibo antenna will be completed this spring, providing dozens of Toutatis-quality detections per year, spacecraft-quality images of the closest approachers, and hundred-pixel images of dozens of main-belt asteroids ( 9 ).1997 December 19, Erik Asphaug, “PLANETARY SCIENCE: Enhanced: New Views of Asteroids”, in Science, volume 278, number 5346, →DOI, pages 2070–2071
   • We have some close approachers," he says, "but not one that would have an impact trajectory."2005 June 3, Ted McClelland, “Something Big Is Out There”, in Chicago Reader

   Synonyms:

   earth approacher