This term may be used in a couple of different contexts. In the first place, it could describe someone who is set to inherit from a person under a will or through intestate succession. Secondly, a beneficiary is one for whose benefit a trust is created. The beneficiary of a trust holds equitable title to the assets held in the trust. This means that the beneficiary has the right to use and enjoy the property held in trust.
Beneficiaries in either context may be children, other family members, charities, foundations, and any other type of person or entity, so long as they are sufficiently defined in the estate planning documents.