受験の難単語メモ（９）tantamount

慶應大の長文に次のような一文がある。

（１）When, not so many decades ago, learning that one had TB was tantamount to hearing a sentence of death - as today, in the popular imagination, cancer equals death - it was common to conceal the identity of their disease from tuberculars and, after they died, from their children. 

tantamountは「等しい、同等の」の意の形容詞で、上の例のようにtantamount toの形で使う。Cambridgeの定義ではbeing almost the same or having the same effect as something, usually something badとなっており、usually something badというのが参考になる。上の例でもそのようになっている。ロングマンでもif an action, suggestion, plan etc is tantamount to something bad, it has the same effect or is almost as badとある。Cambridgeから例を一つ。

（２）Her refusal to answer was tantamount to an admission of guilt.

「答えることを彼女が拒んだのは、罪を認めたようなものだ」という感じだろうか。上の定義におけるalmostもポイントだろう。全く同じというよりも、ほぼほぼ同じ、という感じ。

ところで、辞書の例文では（２）のような「罪を認めたようなもの」系の例文がやたらと多い。そんな使い方ばかりなのかと思ってCOCAで検索したみると、別にそういうことはなさそう。

Cambridgeでは類義語にequivalentが挙がっている。Merriam-Websterでも定義はequivalent in value, significance, or effectとなっている。こちらのequivalentは受験でも頻出の単語。

（３）I would put the English word on one side of a card and the Japanese equivalent on the other. （センター試験）［名詞］

（４）A simple oil change for your car, for example, costs the equivalent of $25 at some gasoline stations, while buying the supplies to do it yourself costs at least $20, meaning it is cost-efficient to let the gasoline station do it for you.（慶應）［名詞］

（５） Economists estimate that by 2025, with current water use patterns and the growing population, water shortage will cut global food production by 350 million tons a year. That is the equivalent of a loaf of bread every week for every person on the planet. （甲南大）［名詞］

（６）As we know from the Institute of Medicine reports and others, medical errors and health-care-associated conditions lead to 200,000 preventable deaths per year in this country alone. That's the equivalent of 20 large jet airliners crashing every week with no survivors.（順天堂大）［名詞］

（７） Even so, 80 million people each year are added to the world's population, a number roughly equivalent to the population of Germany, Vietnam or Ethiopia. （専修大）［形容詞］

（８） They found that only 46 percent of those who lost a ticket were willing to buy another ticket, whereas 88 percent of those who lost an equivalent amount of cash were willing to buy a ticket. （東洋大）［形容詞］

（９）In Western cultures, to look directly into another person's eyes is equivalent to saying, "I'm open to you ― let the action begin." （拓殖大）［形容詞］

最後の例はtantamountの典型的な使い方に近い気がするが、equivalentはどちらかというと他の例のように「（数値・割合などの点で）等しい／相当する」という使い方が多い気がする。（３）のように「（異なる言語（国）の間などで）対応するもの（言葉）」という使い方も多い気がするが、似たような使い方はcounterpartという単語がある。こちらも受験でもよく出てくる気がする。

（１０）High performing students in less developed regions face a much different future from their counterparts' in wealthier areas. （青学）

こちらの単語は「人」に使うことが多い。なお、次のような表現もある。

（１１）The term was invented by economists to help explain why people are not as shrewd in bargaining as they could be, in theory, when they possess information that their opposite number does not. （大阪市立大）

opposite numberはcounterpartの類義表現であり、面白い言い方だなと思う。