Source : Webster's Revised Unabridged Dictionary (1913)

Monish \Mon"ish\, v. t. [OE. monesten. See {Admonish},
   {Monition}.]
   To admonish; to warn. See {Admonish}. [Archaic] --Ascham.

Source : WordNet®

monish
     v 1: warn strongly; put on guard [syn: {caution}, {admonish}]
     2: admonish or counsel in terms of someone's behavior; "I
        warned him not to go too far"; "I warn you against false
        assumptions"; "She warned him to be quiet" [syn: {warn}, {discourage},
         {admonish}]