undercut

Concise Oxford English Dictionary © 2008 Oxford University Press:
undercut/ʌndəˈkʌt/

▶verb (undercuts, undercutting; past and past part. undercut)

• 1 offer goods or services at a lower price than (a competitor).

• 2 cut or wear away the part under (something, especially a cliff).

  ■ cut away material to leave (a carved design) in relief.

• 3 weaken; undermine.

• 4 Tennis strike (a ball) with backspin so that it bounces high on landing.

▶noun

• 1 a space formed by the removal or absence of material from the lower part of something.

  ■ N. Amer. a notch cut in a tree trunk to guide its fall when felled.

• 2 Brit. the underside of a sirloin of beef.