Definitions of - the contesting states
the contracting states
a depend state
a depositary state

the contesting states- two states or two conditions or two people etc opposing each other

the contracting states- two states or two conditions or two people etc concuring each other

depositary state is some kinda organisation to which multilateral treat is entrusted which means this organisation is responsibke to treat some countries or such kinda organisation

dependent state is the state government or organisation which depends on another country or organisation and do not have enough power to control everything (e.x Russia is federation it includes several countries in it and these countries is dependent to Russia)