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.