day

• n. 一日；期間；昼間
• adv. 毎日；しばしば日中
• adj.昼間; 日々
• n. （デイ）人の名前；（E.F.S.）ダイ；（ベト）ダイ；（アラブ、トルコ）ダイ

PIE *dhegwh の「燃える」「輝く」から。語源的には fever, yester と同じ。

day

day: [OE] Day and its Germanic relatives (German tag, Dutch, Danish, and Swedish dag, and Gothic dags) come from a prehistoric Germanic *dagaz. It seems likely that the ultimate source of this was the Indo-European base *dhegh-, which also produced Sanskrit dah- ‘burn’ and nidāgha- ‘heat, summer’, and that the underlying etymological meaning of day is thus ‘time when the sun is hot’.
=> dawn

day (n.)

Old English d?g "day," also "lifetime," from Proto-Germanic *dagaz "day" (cognates: Old Saxon, Middle Dutch, Dutch dag, Old Frisian dei, Old High German tag, German Tag, Old Norse dagr, Gothic dags), according to Watkins, from PIE *agh- (2) "a day" considered as a span of time. He adds that the Germanic initial d- is "of obscure origin."

Not considered to be related to Latin dies (see diurnal), but rather to Sanskrit dah "to burn," Lithuanian dagas "hot season," Old Prussian dagis "summer." Meaning originally, in English, "the daylight hours;" expanded to mean "the 24-hour period" in late Anglo-Saxon times. The day formerly began at sunset, hence Old English Wodnesniht was what we would call "Tuesday night." Names of the weekdays were not regularly capitalized in English until 17c. Day off first recorded 1883; day-tripper first recorded 1897. The days in nowadays, etc. is a relic of the Old English and Middle English use of the adverbial genitive.

1. Carpe diem.Seize the day ，boys.Make your lives extraordinary.

人生は楽しいものであるべきで、毎日を捉えて、子供たち、あなたたちの生活を非凡なものにしなければなりません。

映画『死の詩社』

2.On Sunday Cohen lay around the house all day .

コーエン日曜日は一日中家でごろごろしていました。

3.Someone comes in every day to check all is in order.

毎日、すべてが整然としているかどうかをチェックする人がいます。

4.Try these toning exercises before you start the day .

一日の活動を始める前に、これらの体を強くする体操をしてみましょう。

5.Loyalty and support became the bywords of the day .

忠誠と支持は、その時代の人々がよく口にしていた言葉となった。