I recall something of that from the OED. How about the following definition of "assassin," from dict.org? ...same point, in synopsis?
From Webster's Revised Unabridged Dictionary (1913) :
Assassin \As*sas"sin\, n. [F. (cf. It. assassino), fr. Ar.
`hashishin one who has drunk of the hashish. Under its
influence the Assassins of the East, followers of the Shaikh
al-Jabal (Old Man of the Mountain), were said to commit the
murders required by their chief.]
One who kills, or attempts to kill, by surprise or secret
assault; one who treacherously murders any one unprepared for
defense.
Exactly--killers drunk enough on hash to accomplish the abominable. (First English use--Shakespeare in MacBeth)