The Jargon File (version 4.4.7, 29 Dec 2003):

toy language
 n.

    A language useful for instructional purposes or as a proof-of-concept for
    some aspect of computer-science theory, but inadequate for general-purpose
    programming. Bad Things can result when a toy language is promoted as a
    general purpose solution for programming (see bondage-and-discipline
    language); the classic example is Pascal. Several moderately well-known
    formalisms for conceptual tasks such as programming Turing machines also
    qualify as toy languages in a less negative sense. See also MFTL.


The Free On-line Dictionary of Computing (30 December 2018):

toy language

    A language useful for instructional purposes or as
   a proof-of-concept for some aspect of computer-science theory,
   but inadequate for general-purpose programming.  Bad Things
   can result when a toy language is promoted as a general
   purpose solution for programming (see bondage-and-discipline
   language); the classic example is Pascal.  Several
   moderately well-known formalisms for conceptual tasks such as
   programming Turing Machines also qualify as toy languages in
   a less negative sense.

   See also MFTL.

   [Jargon File]

   (1995-05-09)