/ ɪnˈfɪnətɪv; NAmE / noun
( grammar ) the basic form of a verb such as be or run . In English, an infinitive is used by itself, as is swim in She can swim , or with to as in She likes to swim .
see split verb
late Middle English (as an adjective): from Latin infinitivus , from infinitus , from in- not + finitus finished, finite, past participle of finire , from finis end. The noun dates from the mid 16th cent.