1. [adj]  mixed with impurities
2. [v]  corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones; "adulterate liquor"

ADULTERATE is a 10 letter word that starts with A.

1. \A*dul"ter*ate\, v. t. [imp. & p. p. {Adulterated};
   p. pr. & vb. n. {Adulterating}.] [L. adulteratus, p. p. of
   adulterare, fr. adulter adulterer, prob. fr. ad + alter
   other, properly one who approaches another on account of
   unlawful love. Cf. {Advoutry}.]
   1. To defile by adultery. [Obs.] --Milton.
   2. To corrupt, debase, or make impure by an admixture of a
      foreign or a baser substance; as, to adulterate food,
      drink, drugs, coin, etc.
            The present war has . . . adulterated our tongue
            with strange words.                   --Spectator.
   Syn: To corrupt; defile; debase; contaminate; vitiate;
        sophisticate.
   

2. \A*dul"ter*ate\, v. i.
   To commit adultery. [Obs.]
   

3. \A*dul"ter*ate\, a.
   1. Tainted with adultery.
   2. Debased by the admixture of a foreign substance;
      adulterated; spurious. -- {A*dul"ter*ate*ly}, adv. --
      {A*dul"ter*ate*ness}, n.