Meaning of INFINITIVE in English

[in.fin.i.tive] adj [ME infinityf, fr. LL infinitivus, fr. L infinitus] (15c): formed with the infinitive -- adv

[2]infinitive n (1530): a verb form normally identical in English with the first person singular that performs some functions of a noun and at the same time displays some characteristics of a verb and that is used with to (as in "I asked him to go") except with auxiliary and various other verbs (as in "no one saw him leave")

Merriam-Webster English vocab.      Английский словарь Merriam Webster.