Verb

(undermin)

To dig underneath (something), to make a passage or for destructive or military purposes; to sap.

* 2009 , (Diarmaid MacCulloch), A History of Christianity , Penguin 2010, p. 312:

Martin, for instance, had on one occasion undermined a tree sacred to old gods, then stood in the path of its fall, but forced it to fall elsewhere by making the sign of the Cross.

(figuratively) To weaken or work against; to hinder, sabotage.

* {{quote-news, year=2012, date=April 19, author=Josh Halliday, work=the Guardian

, title= Free speech haven or lawless cesspool – can the internet be civilised? , passage=The growing use of social media to spread anger and dissent in the Arab world has been hailed by western governments as one of the chief justifications for a completely unfettered internet. The US is reportedly funding the secret rollout of technology in Iran in an effort to undermine internet censors in the country.}}

Verb

(en verb)

To prevent; to halt; to cause to fail; to foil; to frustrate.

* South

The proposals of the one never thwarted the inclinations of the other.

* , chapter=22

, title= The Mirror and the Lamp , passage=Not unnaturally, “Auntie” took this communication in bad part.

* {{quote-book, year=2006, author=(Edwin Black), title=Internal Combustion

, chapter=2 citation , passage=More than a mere source of Promethean sustenance to thwart the cold and cook one's meat, wood was quite simply mankind's first industrial and manufacturing fuel.}}

* {{quote-news, year=2011, date=December 10, author=David Ornstein, work=BBC Sport

, title= Arsenal 1-0 Everton , passage=Everton were now firmly on the back foot and it required some sharp work from Johnny Heitinga and Phil Jagielka to thwart Walcott and Thomas Vermaelen.}}

(obsolete) To move across or counter to; to cross.

* (John Milton) (1608-1674)

Swift as a shooting star / In autumn thwarts the night.