The phrase "undercut your" is correct and usable in written English.
It can be used when discussing actions that undermine or weaken someone's position, authority, or efforts.
Example: "His comments were intended to undercut your confidence in the project."
Alternatives: "weaken your" or "undermine your".
Take care that nothing you say online will undercut your credibility as a journalist.
In most businesses, if you want to undercut your competitor, you reduce your prices below theirs.
So that seems to undercut your timetable argument, once you get into the contest phase from the protest phase.
The adversary system means that you're out to, within the rules of the game, undercut your adversary's credibility, embarrass him or her, make your client prevail and not theirs.
"You can disagree in private, but you're not going to air the disagreements publicly and you're not going to undercut your sibling — or you'll pay for it at the dinner table".
"Certainly if you undercut your own leadership, that shortens the honeymoon and could possibly even cripple the administration," said Representative Jim Cooper of Tennessee, a Democrat and member of the fiscally conservative Blue Dog Coalition who opposed the Clinton plan and has criticized current efforts.
Undercutting your competition is also inadvisable, according to Dawn Baird of communication consultancy Sensei.
"You're kind of undercutting your neighbor," said Deanna Kory, a senior vice president at the Corcoran Group.
But if someone's behavior is undercutting your performance and directly affecting your ability to get your job done, you should address it.
In a letter to Mr. Obama in Newsweek last month, Mr. Rove advised him to do more to work across party lines in the Senate because "your lack of achievements undercuts your core themes".
It may come as a surprise, then, to find out that your £10 is more likely to go towards fixing that broken table base, or undercutting your waiter's minimum wage, than it is to be given as a tip.
