Definition of 'Concealment'
As it relates to insurance, the act of purposefully not reporting information that would affect the issuance or rate of an insurance contract.
If the information cannot be known to the insurer and is known to be material by the insured, concealment of that information can give the insurer grounds to nullify the contract or not pay out on claim related to that material information.
Investopedia explains 'Concealment'
When it comes the potential voiding of an insurance contract, it doesn't matter if somebody lies when asked a question (misrepresentation), or isn't asked a specific question and the information is simply withheld (concealment). Both are considered fraudulent and give the insurer grounds to void the contract.