or

或、或者、还是

You can pay by credit card or in cash at the counter.

你可以在柜台刷卡或付现。

否则、不然、要不然常用 or else

Leave now, or you'll miss the last train home.

现在就走，不然你会错过回家的末班车。

也不、或用于否定句

She doesn't drink coffee or tea after six.

她六点以后不喝咖啡也不喝茶。

大约、左右表约数

The whole repair should take a day or two.

整个维修大概一两天就好。

也就是、即、换句话说用于改述

He studies cetaceans, or whales and dolphins.

他研究鲸豚类，也就是鲸鱼和海豚。

手术室美式，缩写 OR

The patient was taken straight to the OR.

病人被直接送进手术室。