Definition of undercut | Bee Dictionary of English

n the material removed by a cut made underneath
n the tender meat of the loin muscle on each side of the vertebral column
n a notch cut in the trunk of tree in order to determine the direction of its fall
n (sports) a stroke that puts reverse spin on the ball
n a cut made underneath to remove material
v sell cheaper than one's competition
v cut away material from the underside of (an object) so as to leave an overhanging portion in relief
v cut away the underpart of
undercut a vein of ore
v strike (the ball) in golf, tennis, or hockey obliquely downward so as to give a backspin or elevation to the shot
v cut obliquely into (a tree) below the main cut and on the side toward which the tree will fall

With Grassley bailing out too, the only Republicans who might side with the Democrats now are Maine's Olympia Snowe and Susan Collins though their GOP street cred is undercut .
If he were to jump ship, the ensuing shift of power to Republicans would scramble the politics of the war in Iraq, undercut the Democrats' national agenda and potentially weaken .
But the Federal Court's verdict on Joy's case, which represented her last legal recourse, may undercut that reputation.

Gazette.Net: Parents at Silver Spring school worry schedule change will dissipate progress
Parents at Silver Spring International Middle School worry that a scheduling change will undercut the academic progress the school has made in the past decade.
June 12, 2013 - Gazette.net
Sony Has Microsoft's Xbox One in Its Crosshairs
On Monday night, Sony undercut Microsoft by announcing that not only will the new PlayStation 4 be $100 cheaper than the Xbox One, it also will avoid digital rights management controls.
June 11, 2013 - The Motley Fool
E3: Microsoft's rough day in L.A.
LOS ANGELES -- Despite the best efforts of Microsoft's army of marketers and publicists preparing for the E3 game show, Monday was a little rocky for the company. First there were audio glitches during the Xbox One demo that were so bad Electronic Arts nearly walked off the stage while presenting "Battlefield 4," one of the biggest games in the event. Then Sony dramatically undercut the price of ...
June 11, 2013 - Seattle Times

Barack Obama in FOXNews
Afghanistan has an elected government, but it is undermined by corruption and has difficulty delivering basic services to its people,Obama said. "The economy is undercut by a booming narcotics trade that encouraged criminality and funds...
John McCain in International Herald Tribune
McCain told reporters he didn't care if Obama's trip was stealing attention and "doesn't in the slightest undercut" his own message.
Dana Perino in Chicago Tribune
Before the vote, White House spokeswoman Dana Perino said, "This and other provisions would place freedom and democracy in Iraq at grave risk, embolden our enemies and undercut the administration's plans to develop the Iraqi economy. If this...