nonstatutory,adj. 1. Enforceable by some legal precept other than enacted law, such as precedent or trade custom. 2.Patents. Unpatentable for not meeting some statutory requirement, e.g., novelty, utility, nonobviousness, or enabling description. 3.Patents. Of or relating to an equitable defense to an infringement claim, esp. estoppel, inequitable conduct, or laches.

[Blacks Law 8th]