BASE jump (bās)
n.
A parachute jump from high structures and precipitous earth formations, typically from heights of 305 meters (1,000 feet) or less.

[B(UILDING) + a(ntenna tower) + S(PAN)¹ + E(ARTH) + JUMP.]

BASE-jump BASE'-jump' v.
BASE jumper BASE jumper n.

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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