Infinitive

1. имя существительное [лингвистика] инфинитив, неопределённая форма глагола 2. прилагательное неопределённый

Большой англо-русский словарь

Infinitive

I. adjective Etymology: Middle English infinityf, from Late Latin infinitivus, from Latin infinitus formed with the infinitive • infinitively adverb II. noun 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's Collegiate Dictionary