The common verbal-noun pattern for an unaugmented quadriliteral is فَعْلَلَة. Additional source examples include:
Word / formMeaning / explanation
دَحْرَجَةrolling something.
زَعْفَرَةcolouring with saffron.
عَسْكَرَةforming or assembling an army.
Their roots are d-ḥ-r-j, z-ʿ-f-r and ʿ-s-k-r respectively. All four radicals occupy the four verbal template positions. The final tāʾ marbūṭah is part of the verbal-noun pattern, not a fifth root consonant.