One that never terminates (that is, the machine {spin}s or {buzz}es forever and goes {catatonic}). There is a standard joke that has been made about each generation's exemplar of the ultra-fast machine: "The Cray-3 is so fast it can execute an infinite loop in under 2 seconds!"
[glossary]
[Reference(s) to this entry by made by: {Alderson loop}]