What does tantamount mean?
Tantamount means equal or equivalent in effect, value, or significance, and it is almost always followed by “to.” For example, treating a warning as tantamount to ignoring it makes a comparison between the warning and the conduct it was meant to prevent. The word is especially common in formal discussion, legal argument, diplomacy, journalism, and workplace communication, where it concisely identifies two actions or positions as having the same practical meaning. Although it can sometimes suggest a close or practical equivalence rather than perfect identity, its central force is that the second thing amounts to the first. In everyday use, “tantamount to” is often followed by a noun, gerund, or that-clause: “tantamount to an admission,” “tantamount to declaring war,” or “tantamount to saying nothing.” The word is useful because it moves beyond literal measurement and compares significance, consequences, or implied meaning. It is formal in register but familiar and readily understood in modern British and American English.
adjectiveEqual or equivalent in meaning, effect, value, or significance.
- Equal or equivalent in meaning, effect, value, or significance.
"His refusal to respond was tantamount to an admission of guilt."
"Silencing the report would be tantamount to suppressing evidence."
"In diplomatic language, the warning was tantamount to a declaration of war."
Its literal plumbing is a curiosity: French tant (“so much”) plus amount produced a word whose earliest sense was “so much amount.”
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does tantamount come from?
The word entered English in the 17th century, formed from French tant (“so much”) and amount (“sum”). Amount comes through Old French mont from Latin montem, the accusative of mons (“mountain”), while tant comes from Latin tam (“so”). Its literal sense was “so much amount,” but it came to mean “equal in amount or effect.”
How tantamount is actually used
Formal and sometimes legal or diplomatic in tone, but standard and readily understood in modern British and American English. It is normally used predicatively as “tantamount to” rather than before a noun.
Easily confused with tantamount
Tantamount means equivalent in effect or significance, whereas paramount means supreme or of greatest importance.