1590s, "phantom, ghost," a figurative use from Latin umbra "shade, shadow" (see umbrage). Astronomical sense of "shadow cast by the earth or moon during an eclipse" is first recorded 1670s. Meaning "an uninvited guest accompanying an invited one" is from 1690s in English, from a secondary sense among the Romans. Related: Umbral.
例文
1. This includes the continuous survey of umbra and penumbra of the sunspot.
これには、太陽黒点の本影と半影の持続的な観測が含まれている。
2.This a lighter area between the umbra and the edge of a shadow.
これは、影と影のエッジの間の明るい領域です。
3.Only moon umbra totally puts on earth,the shadow area can watch the eclipse.
月の本影が地球表面に投影されている場合にのみ、その領域にいる人が日食を観測することができる。
4. Umbra -You need Samples values equal to or greater than 2 to see any influence of this button.