To clarify the meaning of the term 'prevailing party' with regard to the recovery of attorneys' fees.

Catalyst Theory Restoration Act of 2018 This bill defines the term "prevailing party" for purposes of determining an award of attorney's fees against the federal government in judicial or administrative proceedings. Specifically, a prevailing party includes a party whose claim or defense motivates (i.e., catalyzes) the opposing party to voluntarily provide a significant part of the relief sought.