Why this word is great
ESTOPPEL — [Noun] A legal principle in equity that prevents a party from asserting a right or claim that contradicts their previous conduct or statements, to prevent injustice. From Middle English stoppel, stoppell, from Old French estoupail, estopail ("bung, cork"), from estoper ("to stop up"), from Latin stuppa ("flax, tow"), from Ancient Greek στύππη (stuppē, "flax, hemp"). Unlike "waiver" (a deliberate surrender of rights) or "res judicata" (a final judicial bar), estoppel is the silent arbiter of consistency, binding parties to their own past acts. It is the landlord who cannot deny a tenant’s lease after accepting rent, the government estopped from reclaiming land long treated as public, or the parent who, having nodded at a promise, finds themselves legally wedded to it—a cork forced into the bottle of human fickleness, lest fairness leak away.