Caveat emptor is Latin for "Let the buyer beware" (from caveat, "may he beware", the subjunctive of cavere, "to beware" + emptor, "buyer"). Generally, caveat emptor is the contract law principle that controls the sale of real property after the date of closing, but may also apply to sales of other goods. The phrase caveat emptor arises from the fact that buyers typically have less information about the good or service they are purchasing, while the seller has more information. The quality of this situation is known as 'information asymmetry'. Defects in the good or service may be hidden from the buyer, and only known to the seller.
Dictionary source: Law Dictionary
English to English translation of Caveat emptor
Lat. 'buyer beware.' This rule used to generally apply to all sales, especially between individuals. It gives the buyer full responsibility for determining the quality of the goods in question. The seller generally has no duty to offer warranties or to disclose defects in the goods.
This concept has been modified by various state and federal laws as well as principles such as consumer protection and disclosure statutes and implied warranties - i.e., of use, safety, etc. However, such things may provide incentive and redress, but not full protection against miscreants, so it is best to always be cautious.
Let the purchaser take heed; that is, let him see to it that the title he is buying is good. This was/is a rule of the common law applicable to the sale and purchase of lands and other real estate. If the purchaser pay the consideration money he cannot, as a general rule in every case, recover it back after the deed has been executed; except in cases of fraud, or by force of some covenant in the deed which has been broken. The purchaser, if he fears a defect of title, has it in his power to protect himself by proper covenants and if he fails to do so the law provides for him no remedy.
This rule was severely assailed as being the instrument of falsehood and fraud; but it was too well established to be disregarded and is still operative in many situations.
This entry contains material from Bouvier's Legal Dictionary, a work published in the 1850's.