Word / formMeaning / explanation
بَعْثَرَperfect verb: he scattered.
بَعْثَرَةverbal noun: scattering.
اِقْشَعَرَّperfect: hair stood on end.
اِقْشِعْرَارverbal noun: the state of hair standing on end.
تَسَرْبَلَperfect: he put on a garment.
تَسَرْبُلverbal noun: putting on a garment.
A verbal noun preserves the basic action or state without identifying a subject and tense as a finite perfect or imperfect does.