足あし元もとをすくう

expression, godan verb (-u)

trip someone up; pull the rug out from under

Idiomatic expression meaning to catch someone off guard or undermine them, often by exploiting a weakness. Note: This is a common but technically incorrect variant of 足をすくう; the standard form uses 足 (あし) without 元.

See also: 足をすくう (あしをすくう)

• 彼かれの質しつ問もんは私わたしの足あし元もとをすくうようなものだった。

  His question was like pulling the rug out from under me.

• 油ゆ断だんしていると、足あし元もとをすくわれるぞ。

  If you let your guard down, you'll be tripped up.