A noun formed from a verb (such as the `-ing' form of an English verb when used as a noun) WordNet 3.0 & Open English WordNet

In linguistics, a gerund is any of various nonfinite verb forms in various languages; most often, but not exclusively, one that functions as a noun. Wikipedia

An element of syntax in grammar Wikipedia Disambiguation

Verb form Wikidata

A verbal form that functions as a verbal noun. OmegaWiki

In some languages such as Dutch, Italian or Russian, a verbal form similar to a present participle, but functioning as an adverb to form adverbial phrases or continuous tense. These constructions have various names besides gerund, depending on the language, such as conjunctive participles, active participles, adverbial participles, transgressives, etc. Wiktionary