I've never heard of monotonic being used for two (input) variables, but I suppose it would mean that, for each fixed value of y, u is a monotonic function of x, and for each fixed value of x, u is a monotonic function of y (and I expect they'd need to be either both monotonic increasing or both monotonic decreasing).
Business Trust Law & Legal Definition. Business trust is a form of business organization which is similar to a corporation, in which investors receive transferable certificates of beneficial interest.n some states, a business trust is subject to the laws of trusts whereas in other states the laws of corporations or partnerships govern its existence.
SPDR Gold Trust (the Trust) is an investment trust. The investment objective of the Trust is for the Shares to reflect the performance of the price of gold bullion, less the Trust's expenses. The Trust's business activity is the investment of gold. The Trust creates and redeems Shares from time to time, but in one or more Baskets (a Basket equals a block of 100,000 Shares).