tantamount

American  

[tan-tuh-mount] / ˈtæn təˌmaʊnt /

adjective

1. equivalent, as in value, force, effect, or signification.

   His angry speech was tantamount to a declaration of war.

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tantamount British  

/ ˈtæntəˌmaʊnt /

adjective

1. as good (as); equivalent in effect (to)

   his statement was tantamount to an admission of guilt

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Related Words

See equal.

Etymology

Origin of tantamount

First recorded in 1635–45; adjective use of obsolete noun, “that which amounts to as much, something equivalent,” itself a noun use of an obsolete verb, “to amount to as much,” from Anglo-French tant amunter or Italian tanto montare “to amount to as much,” from Latin tantum, neuter of adjective tantus “of such size, so great”; tanto, amount

Explanation

When something is tantamount to another thing it is essentially its equivalent. For some animal activists, wearing fur is tantamount to murder. Tantamount often refers to an action or thing being compared to another greater action or quality, as in, “Missing your finals is tantamount to dropping out of college.” While the two sides are essentially equal, you would not say, "Dropping out of school is tantamount to missing your finals.” A related word is paramount, which means “the highest” or “primary.”

Example Sentences

Fadiah wrote on X that being denied entry was "tantamount to a deliberate attack on my scholarly work".

From BBC • Mar. 27, 2026

Eritrea, however, sees Ahmed’s maritime aspirations as tantamount to a threat of military aggression.

From The Wall Street Journal • Mar. 7, 2026

"For his age, this is tantamount to a life sentence -- an extremely severe punishment," she said.

From Barron's • Feb. 9, 2026

It was tantamount to sticking his injured hand in a lion’s mouth.

From Los Angeles Times • Dec. 4, 2025

Thanks to the number-shape duality, to the Greeks counting was tantamount to measuring a line.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Related Words

• commensurate
• identical