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tr.v. un·der·ran (-răn′), un·der·run, un·der·run·ning, un·der·runs
1. To run, pass, or go beneath.
2. Nautical To haul (a line or cable) onto a boat for inspection or repair.
1. Something that runs under, as:
a. An amount or a quantity produced that is less than what has been estimated.
b. The difference between this amount or quantity and what has been estimated.
2. An undercurrent.
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.


vb, -runs, -running, -ran or -run
1. (tr) to go beneath
2. (Nautical Terms) (tr) to check the hull of (a boat)
3. (Nautical Terms) (tr) to retract (a net or trawl)
4. (Broadcasting) (intr) (of a broadcast programme) to fall short of scheduled time
5. the degree to which a programme underruns
6. the action of going beneath
7. an undercurrent
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌʌn dərˈrʌn)

v. -ran, -run, -run•ning,
n. v.t.
1. to run, pass, or go under.
2. something that runs or passes underneath, as a current.
3. an instance of costing less than estimated.
4. a production run below the quantity ordered.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in classic literature ?
The moonlight turns the lower strata to silver without a stain except where our shadow underruns us.
Boston Federal Reserve president Eric Rosengren says in a speech today at the Economic Club of New York,"Given that inflation has underrun the target over the last several years, it is wise to admit to some uncertainty about this part of the forecast.
Trucks are increasingly safe, thanks in particular to underrun bars, powerful retarders and drivers
The rightmost columns of Table 2 report the underrun or overrun percentage for each log as well as an overall average.
The truck also comes with safety features such as ABS, Front Underrun Protection System (FUPS), Rear Underrun Protection System (RUPS), among others.
The series is suitable for use in applications from tipper and reefer trucks to general cargo vehicles, and includes a range of safety features, including an anti-lock braking system, front underrun protection system (FUPS) and rear underrun protection system (RUPS).
The overall risk assessment is finished here by discussing the contingencies in relation to the probability of overrun / underrun the cost estimate for the implementation of project strategy [9], [10] (without design costs).
The Saudi Standards, Metrology and Quality Organisation (SASO) released the technical regulations for the underrun protective devices in trucks, bearing the following technical specifications numbers: SASO-GSO 2112:2012 "Motor Vehicle- front underrun protective devices in trucks and its testing methods; (SASO-GSO 2113:2012) "Motor Vehicles-Lateral Protection of Truck and Trailer and its testing methods"; and SASO-GSO 2114:2012) "Motor Vehicles Rear underrun protective devices for truck and trailer and its testing methods".
Evans said, 'My forecast does not see inflation rising to our 2 percent target until 2018 -- for me, that's too far down the road given how long we have underrun our target.