more formal term for on, especially in abstract senses: onのよりかたい語。特に抽象的な場面で

e.g. it was based upon two principles: それは2つの原理に基づいていた。

e.g. a school's dependence upon parental support.: 学校の親の支援への依存

Middle English: from up + on, suggested by Old Norse upp á.

The preposition upon has the same core meaning as the preposition on. Upon is sometimes more formal than on, however, and is preferred in the phrases once upon a time and upon my word, and in uses such as row upon row of seats and Christmas is almost upon us.

前置詞uponは前置詞onと同じ中核的な意味を持っている。uponはonよりもかたいことがあるが、once upon a timeやupon my word、「幾重にも並んだ座席」や「もうすぐクリスマスだ」のような用法において好まれる。