I read a paper today that kept using "multistrata" to describe an object with multiple layers. For example:
I love multistrata cakes.
This sounds wrong to my ear, I think "multistratum" sounds better, even though the plural of stratum is strata. Certainly "multilayer cakes" sounds better than "multilayers cakes", which is the analogue to "multistratum" and "multistrata".
Are there definitive rules for forming adjectives from Latin nouns?