An error that causes a program to terminate when it is
being run. SOURCE - UK Tech Glossary
An error that occurs during the execution of a program. In
contrast, compile-time errors occur while a program is
being compiled. Runtime errors indicate bugs in the
program or problems that the designers had anticipated but
could do nothing about. For example, running out of memory
will often cause a runtime error. SOURCE - Webopedia
When a program is running, or executing, it is said to be
in runtime. The term is mostly used by software developers
to specify when errors in a program occur. A "runtime
error" is an error that happens while the program is
executing. For example, if a program told you that 2 + 2
was 5000, that would be a runtime error. A memory leak,
where the program sucks up excessive amounts of system
memory is also a runtime error. The other major type of
program error is a compile-time error, where the
application will not even compile into an executable
program. Examples of compile-time errors are syntax errors
in the program code and file linking errors. SOURCE -
Sharpened Glossary