Without consulting Blacks or any dictionary... it is my understanding that...
A corporation (incorporation) is a franchise license given by the state to a group or individual in order to conduct commerce with some tribute (tax) given back to the State for usage of said franchise and limited liability protection. [Juristic person].
A trust is an arrangement where money and property are managed on behalf of another involving such parties as settlor, trustees, and beneficiaries. I would think a common law trust is private law. Anything filed with the State would be come public law (domain).
Corporation:
http://en.wikipedia.org/wiki/Corporation
Trust:
http://en.wikipedia.org/wiki/Trust_law
Of course, there are an infinite amount of nuisances to both definitions depending on context and interpretation e.g. federal corporations, pure trust, municipal corporations,etc.
Regards,
netwrkranger