The doctrine of estoppel under Section 115 of the Indian Evidence Act, 1872 means that:

Section 115 of the Indian Evidence Act embodies the doctrine of estoppel, which prevents a person from denying a representation made by their act, conduct, or omission when another person has believed it and acted upon it. In simple terms, if A causes B to believe a fact and B changes position on that basis, A cannot later turn around and deny that fact in court. Estoppel is treated in Indian law as a rule of evidence, not as a source of title or an independent cause of action. It also does not mean that every admission becomes conclusive proof, because admissions are generally not conclusive though they may operate as estoppel in appropriate cases.