1. [n]  the mental faculty or power of vocal communication; "language sets homo sapiens apart from all other animals"
2. [n]  the cognitive processes involved in producing and understanding linguistic communication; "he didn't have the language to express his feelings"
3. [n]  a systematic means of communicating by the use of sounds or conventional symbols; "he taught foreign languages"; "the language introduced is standard throughout the text"; "the speed with which a program can be executed depends on the language in which it is written"
4. [n]  a system of words used in a particular discipline; "legal terminology"; "the language of sociology"
5. [n]  the text of a popular song or musical-comedy number; "his compositions always started with the lyrics"; "he wrote both words and music"; "the song uses colloquial language"
6. [n]  communication by word of mouth; "his speech was slurred"; "the telephone greatly increased the range of speech communication"; "he uttered harsh language"; "he recorded the spoken language of the streets"

Language
A study of the sound, form, and structure of language and the way in which different languages relate to, and influence one another

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1. \Lan"guage\, n. [OE. langage, F. langage, fr. L. lingua
   the tongue, hence speech, language; akin to E. tongue. See
   {Tongue}, cf. {Lingual}.]
   1. Any means of conveying or communicating ideas;
      specifically, human speech; the expression of ideas by the
      voice; sounds, expressive of thought, articulated by the
      organs of the throat and mouth.
   Note: Language consists in the oral utterance of sounds which
         usage has made the representatives of ideas. When two
         or more persons customarily annex the same sounds to
         the same ideas, the expression of these sounds by one
         person communicates his ideas to another. This is the
         primary sense of language, the use of which is to
         communicate the thoughts of one person to another
         through the organs of hearing. Articulate sounds are
         represented to the eye by letters, marks, or
         characters, which form words.
   2. The expression of ideas by writing, or any other
      instrumentality.
   3. The forms of speech, or the methods of expressing ideas,
      peculiar to a particular nation.
   4. The characteristic mode of arranging words, peculiar to an
      individual speaker or writer; manner of expression; style.
            Others for language all their care express. --Pope.
   5. The inarticulate sounds by which animals inferior to man
      express their feelings or their wants.
   6. The suggestion, by objects, actions, or conditions, of
      ideas associated therewith; as, the language of flowers.
            There was . . . language in their very gesture.
                                                  --Shak.
   7. The vocabulary and phraseology belonging to an art or
      department of knowledge; as, medical language; the
      language of chemistry or theology.
   8. A race, as distinguished by its speech. [R.]
            All the people, the nations, and the languages, fell
            down and worshiped the golden image.  --Dan. iii. 7.
   {Language master}, a teacher of languages. [Obs.]
   Syn: Speech; tongue; idiom; dialect; phraseology; diction;
        discourse; conversation; talk.
   Usage: {Language}, {Speech}, {Tongue}, {Idiom}, {Dialect}.
          Language is generic, denoting, in its most extended
          use, any mode of conveying ideas; speech is the
          language of articulate sounds; tongue is the
          Anglo-Saxon tern for language, esp. for spoken
          language; as, the English tongue. Idiom denotes the
          forms of construction peculiar to a particular
          language; dialects are varieties if expression which
          spring up in different parts of a country among people
          speaking substantially the same language.
   

2. \Lan"guage\, v. t. [imp. & p. p. {Languaged}; p. pr. &
   vb. n. {Languaging}.]
   To communicate by language; to express in language.
         Others were languaged in such doubtful expressions that
         they have a double sense.                --Fuller.
   

1. programming language.

2. natural language.