What does indefeasibly mean?
Indefeasibly is an adverb meaning in a way that cannot be disproved, revoked, or overturned. It is used when describing a claim, principle, right, decision, or commitment that is treated as beyond challenge. The word is especially common in legal and philosophical writing, where the permanence of a rule or the validity of an argument may be at issue. For example, a court might regard a contractual provision as indefeasibly valid, meaning that it cannot be invalidated on the grounds under consideration. Although it is closely related in meaning to irrevocably and incontrovertibly, indefeasibly focuses more specifically on the impossibility of refutation or reversal. The adverb derives from indefeasible, which in turn comes from a Latin root meaning something that can be undone.
adverbIn a manner that cannot be disproved, revoked, or overturned. It describes a claim, right, commitment, or principle that is final beyond challenge.
- In a way that cannot be disproved, revoked, or overturned.
"The witness made an indefeasibly clear distinction between the two accounts."
"The court accepted the clause as an indefeasibly valid condition of the agreement."
"Her commitment to public service remained indefeasibly strong throughout the campaign."
An indefeasible claim cannot be challenged on logical grounds: it is not merely strongly supported, but immune to rebuttal.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does indefeasibly come from?
The word ultimately derives from Latin defeasibilis, meaning liable to be undone or defeated. The prefix in- added a negative meaning, while feasible comes from Latin facere, meaning to do or make. In later English, feasible developed the sense of possible or practicable, and indefeasible acquired its modern sense of impossible to disprove, revoke, or overturn.
Related word forms
How indefeasibly is actually used
This is a formal and comparatively uncommon adverb, used especially in legal, philosophical, and argumentative contexts. It is more emphatic than simply saying that something is certain, because it implies that the claim or principle cannot be challenged or overturned.
Easily confused with indefeasibly
Indefeasible means unable to be disproved or overturned, whereas imperishable means unable to decay or be destroyed.