[1] : The Collaborative International Dictionary of English v.0.48

infinitive \infin"itive\, n. l. infinitivus: cf. f.
   infinitif. see infinite.
   unlimited; not bounded or restricted; undefined.
   1913 webster

   infinitive mood gram., that form of the verb which merely
      names the action, and performs the office of a verbal
      noun. some grammarians make two forms in english: a
      the simple form, as, speak, go, hear, before which to is
      commonly placed, as, to speak; to go; to hear. b the
      form of the imperfect participle, called the infinitive in
      -ing; as, going is as easy as standing.
      1913 webster

   note: with the auxiliary verbs may, can, must, might, could,
         would, and should, the simple infinitive is expressed
         without to; as, you may speak; they must hear, etc. the
         infinitive usually omits to with the verbs let, dare,
         do, bid, make, see, hear, need, etc.; as, let me go;
         you dare not tell; make him work; hear him talk, etc.
         1913 webster

   note: in anglo-saxon, the simple infinitive was not preceded
         by to the sign of modern simple infinitive, but it
         had a dative form sometimes called the gerundial
         infinitive which was preceded by to, and was chiefly
         employed in expressing purpose. see gerund, 2.
         1913 webster

   note: the gerundial ending -anne not only took the same
         form as the simple infinitive -an, but it was
         confounded with the present participle in -ende, or
         -inde later -inge.
         1913 webster
see also:
infinite infinitive mood a b gerund 

[2] : The Collaborative International Dictionary of English v.0.48

infinitive \infin"itive\, n. gram.
   an infinitive form of the verb; a verb in the infinitive
   mood; the infinitive mood.
   1913 webster

[3] : The Collaborative International Dictionary of English v.0.48

infinitive \infin"itive\, adv. gram.
   in the manner of an infinitive mood.
   1913 webster

[4] : WordNet (r) 2.0

infinitive
     adj 1: formed with the infinitive; "an infinitive phrase"
     2: not having inflections to indicate tense
     n : the uninflected form of the verb

Infinitive >> I Words
Infinitive, definition of term: Infinitive
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