except; other than; no other than
Used in the pattern 〜を措いて to single out someone or something as the only option. Often followed by a negative or rhetorical statement. The kanji 措 is rare in modern writing; the kana form おいて is strongly preferred.
See also: をおいて
There is no one other than him who can be entrusted with this job.
この問題を解決できるのは、あなたを措いて他にいない。
There is no one else but you who can solve this problem.
他に means 'besides' or 'in addition', whereas 措いて emphasizes that there is no alternative at all.
Derived from the verb 措く (おく, 'to set aside, to leave'), in the て-form. The kanji 措 is not commonly used in modern Japanese outside this expression.