- Estoppel is defined as a legal principle that stops someone from asserting a truth that is defined as contradictory to an already established truth.
If the court has established in a criminal trial that someone is guilty of murder, the legal doctrine preventing the murderer from denying his guilt in a civil trial is an example of estoppel.
estoppel definition by Webster's New World
Origin: Old French estoupail, stopper, bung ; from estoper: see estop
estoppel definition by American Heritage Dictionary
Origin: Obsolete French estouppail, from Old French estouper, to stop up, from Vulgar Latin *stuppāre; see stop.
estoppel - Business Definition
estoppel - Legal Definition