Cestuy \Ces"tuy\ or Cestui \Ces"tui\, pron. [Norm. F.]

(Law) He; the one.

Cestuy que trust[norm. F.]

, a person who has the equitable and beneficial interest in property, the legal interest in which is vested in a trustee. --Wharton.

Cestuy que use[Norm. F.]

, a person for whose use land, etc., is granted to another.

Source: Webster's Revised Unabridged Dictionary (1913)