Gerund definition

From , from , the gerundive of . In , a verbal noun used for all cases of the infinitive but the nominative.

A verbal form that functions as a verbal noun. (In English, a gerund has the same spelling as a present participle, but functions differently.)

In the phrase ‘Walking is good exercise.’, walking is a gerund.
In some languages such as Italian or Russian, a verbal form similar to a present participle, but functioning as an adverb. These words are sometimes referred to as conjunctive participles.

In the Russian 'Нельзя переходить улицу читая газету.’ (One shouldn’t cross a street while reading a newspaper.), читая ‘while reading’ is a gerund.