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1. A large clasp knife.
2. Sports A dive in the pike position, in which the diver straightens out to enter the water hands first.
v. jack·knifed, jack·knif·ing, jack·knifes
1. To fold or double (something or oneself) like a jackknife.
2. To cut or stab with a jackknife.
1. To bend or fold up like a jackknife: A truck that had jackknifed was blocking the road.
2. To form a 90° angle.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
n, pl -knives
1. (Tools) a knife with the blade pivoted to fold into a recess in the handle
2. (Swimming, Water Sports & Surfing) a former name for a type of dive in which the diver bends at the waist in midair, with the legs straight and the hands touching the feet, finally straightening out and entering the water headfirst: forward pike dive
3. (Automotive Engineering) (of an articulated lorry) to go out of control in such a way that the trailer swings round at an angle to the cab
4. (Swimming, Water Sports & Surfing) to make a jackknife dive
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
n., pl. -knives, n.
1. a large pocketknife.
2. a dive in which the diver bends in midair to touch the toes, keeping the legs straight, and then straightens out.v.i.
3. to bend over from or at the middle; double over like a jackknife.
4. (of a trailer truck) to have the cab and trailer swivel at the linkage until they form a Vshape, as the result of an abrupt stop or accident.
5. (in diving) to perform a jackknife.v.t.
6. to cause to jackknife.
7. to cut with a jackknife.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
Past participle: jackknifed
Collins English Verb Tables © HarperCollins Publishers 2011
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|Noun||1.||jackknife - a large knife with one or more folding blades|
|2.||jackknife - a dive in which the diver bends to touch the ankles before straightening out|
|Verb||1.||jackknife - dive into the water bending the body at the waist at a right angle, like a jackknife|
dive - plunge into water; "I was afraid to dive from the board into the pool"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
B. VI [lorry] → colear
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