Final answer:
The term that describes blocking attempts to change conduct or reassert a previously waived right, especially after reliance by the other party, is known as estoppel.
Step-by-step explanation:
A term that blocks all attempts to change conduct or reassert a right previously waived, and it usually applies after the other party has begun to rely on the conduct or waiver is known as estoppel. It is a legal principle that prevents someone from arguing something contrary to a claim they have previously made or accepted by their actions, especially if this would be to the detriment of another who has relied on the original claim. This relates to the concept of prior restraint insofar as both involve the limitation of actions based on previous conduct, though estoppel is a broader legal doctrine that can apply in various contexts, from contract law to civil rights, whereas prior restraint specifically deals with the prevention of speech or expression before it occurs. Both estoppel and prior restraint are concerned with the idea of fairness and the protection of parties from changes in position that could harm them.