Webster's Revised Unabridged Dictionary · 1913

Undercut

Undercut , noun

The lower or under side of a sirloin of beef; the fillet.

Undercut , transitive verb

1.
To cut away, as the side of an object, so as to leave an overhanging portion.
2.
to sell goods or services at a price below that of (the competition or a competitor's price).
3.
to weaken the effectiveness of; to undermine or sabotage (an activity).
4.
(Forestry) To cut a notch in one side of (a tree) so as to control the direction in which the tree falls when it is felled.

Undercut , past participle (adjectival)

Cut away below.