Dictionary.com
definitions

bushline

[boo sh-lahyn]
noun Canadian.
  1. an airline that flies over sparsely inhabited territory to serve isolated settlements.

Origin of bushline

bush1 + (air)line
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for bush-line

bush-line

noun
  1. NZ the contour at which the growth of the bush ceases
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