a device for protection against the rain, consisting of a stick with a folding frame covered in material at one end and usually a handle at the other, or a similar, often larger, device used for protection against the sun

I felt a few drops of rain, so I put my umbrella up. 我感到有几滴雨点，于是便撑起了雨伞。

I left my umbrella on the bus yesterday. 我昨天把伞落在公交车上了。

a folding umbrella 折叠伞

something that includes or represents a group or range of similar things

He runs a group of companies under the umbrella of Universal Foods. 他经营一组公司，总称为Universal Foods。

The Organization of Islamic Conference is an umbrella organization representing 57 Muslim nations. 伊斯兰国家组织是代表57个伊斯兰国家的机构。

Existentialism was really an umbrella term to lump together the works of several philosophers and writers. 存在主义实际上是一个把几位哲学家和作家的作品归并在一起的总称。