The expression ‘Estoppel ‘is derived from the French word ‘Estoup’ which means “shut the mouth”. When a person tells us something, we generally hear him/her .If he/she says something different or contradicting, we would not hear any more and contradict such statement .Otherwise,we shall comply with it. a person by declaration (act or omission) makes/induces another to believe a thing, can not deny its truth subsequently. The other person cannot be stopped from proceeding upon such declaration. Estoppel is a rule of evidence, by which a person is not allowed to plead the contrary of a fact or state of things, which he/she has formally asserted as existing.
As per the Sec.34 of Evidence Act 2031,”any body who represents to other by word or by writing or by conduct any fact which the other party believes on it and works upon it, the first party is stopped from denying the fact in the suit that follows.”Similarly Sec.115 of Evidence Act 1872,embodies the principle of estoppels. It runs as follows, when one person has, by his declaration, act, or omission intentionally caused or permitted another person to believe, neither he/she nor his/her representative shall be allowed, in any suit or proceeding between himself/herself and such person or his/her representative, to deny the truth of the thing.