【Imposture】 , 【cheat】 ,  【fraud】 ,  【sham】 ,  【fake】 ,  【humbug】 ,  【deceit】 ,  【deception】 ,  【counterfeit】  all mean something which pretends to be one thing in its nature, character, or quality but is really another.

【Imposture】 applies not only to an object but to an act or practice which is passed off to another as genuine, authentic, or bona fide.

【Cheat】 applies chiefly to something or sometimes to someone that wins one's belief in its or his genuineness, either because one is deliberately misled or imposed upon by another or is the victim of illusion or delusion.

【Fraud】 applies to a deliberate, often criminal, perversion of the truth. Applied to a person it may be less condemnatory and suggest pretense and hypocrisy.

【Sham】 applies to a close copy of a thing, especially to one that is more or less obviously a fraudulent imitation.

【Fake】  applies either to a person that represents himself as someone he is not or, more often, to a worthless thing that is represented as being something that it is not;  【fake】  differs from  【fraud】  in not necessarily implying dishonesty in these representations, for a  【fake】 may be a joke or a theatrical device, or it may be a clear 【fraud】 .

【Humbug】 applies to a person or sometimes a thing that pretends or is pretended to be other and usually more important than he or it is, not necessarily because of a desire on the part of the person involved to deceive others but often because he is self-deceived.

【Deceit】  and  【deception】  both apply to something that misleads one or deludes one into taking it for what it is not.

【Deceit】 , however, usually suggests the work of a deceiver or of one that misleads or leads astray.

【Deception】 , on the other hand, often suggests a quality or character in the thing which causes one to mistake it or frankly to take it as other than it really is.

【Counterfeit】 applies to a close imitation or copy of a thing (as a coin, a banknote, or a bond) that depends upon pictorial devices or engraved designs for assurance of its genuineness; the term usually also implies the passing or circulation of such an imitation as if it were genuine. The term is also applicable to a thing or, less often, to a person that passes for something other than it actually or truly is.