| Definition -
A noun that (1) can act as an autonomous common noun and (2) that has been derived from a verb or a verb phrase. e.g. invader is a deverbal noun derived from invade.
1. Verbal nouns (VNs) and deverbal nouns (DVNs) are both formed from verbs, but DVNs differ from VNs in that DVNs operate as autonomous common nouns, while VNs retain verbal characteristics.
For example, gerunds are verbals, not deverbals. Compare:
Fencing is fun. (verbal – an activity, replaceable by the infinitive "to fence")
The white fencing contributes to the neighborhood's character. (deverbal – a common noun, replaceable by other nouns like "bench")