1. The action of keeping something secret; such as, the fraudulent failure to reveal information which someone knows and is aware that in good faith he or she should tell another person or authority: Such concealment can at least cause for a cancellation of a contract by the misled person or be the basis for a civil lawsuit for fraud.

2. A covering that serves to hide or to shelter something.
3. A condition of being hidden.
4. Keeping out of sight and from being seen, found, observed, or discovered.
5. Etymology: from Latin concelare; from con-, "completely" + celare, "to hide".

1. The deliberate hiding, non-disclosure, or suppression of essential facts or circumstances that someone is legally or morally required to reveal; especially, with the intention to deceive or to defraud a person in a contractual arrangement.
2. Concealment, destruction or withholding of, or refusal to give, material evidence which a person has or knows and is legally or morally boung to reveal.

It is normally considered an '"obstruction of justice" which is a criminal offense.

3. A deliberate attempt to withhold information or to conceal an act to avoid a contractual responsibility.

Fraudulent concealment that is applied to health care providers comes up when a treating doctor conceals from an aggrieved patient that a previous treating doctor may have committed malpractice.