aktywiszcze

Etymology
From.

Usage notes
Neologistic neuter constructions are increasingly used by non-binary people to describe themselves. However, they are still uncommon and not recognized by language authorities and most speakers recognize them as either unnatural or derogatory, in part due to the neuter gender usually being used to describe objects, animals, or small children, especially constructions ending in -iszcze, which resembles the augmentative suffix.