The Collaborative International Dictionary of English v.0.48:

Application \Ap`pli*ca"tion\, n. [L. applicatio, fr. applicare:
   cf. F. application. See Apply.]
   1. The act of applying or laying on, in a literal sense; as,
      the application of emollients to a diseased limb.
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   2. The thing applied.
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            He invented a new application by which blood might
            be stanched.                          --Johnson.
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   3. The act of applying as a means; the employment of means to
      accomplish an end; specific use.
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            If a right course . . . be taken with children,
            there will not be much need of the application of
            the common rewards and punishments.   --Locke.
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   4. The act of directing or referring something to a
      particular case, to discover or illustrate agreement or
      disagreement, fitness, or correspondence; as, I make the
      remark, and leave you to make the application; the
      application of a theory.
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   5. Hence, in specific uses:
      (a) That part of a sermon or discourse in which the
          principles before laid down and illustrated are
          applied to practical uses; the "moral" of a fable.
      (b) The use of the principles of one science for the
          purpose of enlarging or perfecting another; as, the
          application of algebra to geometry.
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   6. The capacity of being practically applied or used;
      relevancy; as, a rule of general application.
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   7. The act of fixing the mind or closely applying one's self;
      assiduous effort; close attention; as, to injure the
      health by application to study.
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            Had his application been equal to his talents, his
            progress might have been greater.     --J. Jay.
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   8. The act of making request of soliciting; as, an
      application for an office; he made application to a court
      of chancery.
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   9. A request; a document containing a request; as, his
      application was placed on file.
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WordNet (r) 3.0 (2006):

application
    n 1: the act of bringing something to bear; using it for a
         particular purpose; "he advocated the application of
         statistics to the problem"; "a novel application of
         electronics to medical diagnosis" [syn: application,
         practical application]
    2: a verbal or written request for assistance or employment or
       admission to a school; "December 31 is the deadline for
       applications"
    3: the work of applying something; "the doctor prescribed a
       topical application of iodine"; "a complete bleach requires
       several applications"; "the surface was ready for a coating
       of paint"; [syn: application, coating, covering]
    4: a program that gives a computer instructions that provide the
       user with tools to accomplish a task; "he has tried several
       different word processing applications" [syn: application,
       application program, applications programme]
    5: liquid preparation having a soothing or antiseptic or
       medicinal action when applied to the skin; "a lotion for dry
       skin" [syn: lotion, application]
    6: a diligent effort; "it is a job requiring serious
       application" [syn: application, diligence]
    7: the action of putting something into operation; "the
       application of maximum thrust"; "massage has far-reaching
       medical applications"; "the application of indexes to tables
       of data"

The Free On-line Dictionary of Computing (19 January 2023):

application

   1. application program.

   2. function application.